Адфільтраваць паведамленні Reddit

Фільтруйце паведамленні, якія вы не жадаеце бачыць, у вашай (новай) стужцы Reddit з дапамогай рэгулярных выразаў

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name                 Weed Out Reddit Posts
// @namespace            github.com/JasonAMelancon
// @version              2026-01-14
// @description          Filter posts you don't want from your (new) Reddit feed with regular expressions
// @description:af       Filtreer plasings wat jy nie wil hê nie uit jou (nuwe) Reddit-feed met gewone uitdrukkings
// @description:am       ከ(አዲሱ) Reddit ፊድህ የምታለምን ልጥፎችን በመደበቅ ሐረግ (regular expressions) አጠቃሽ አስወግድ
// @description:ar       قم بتصفية المنشورات التي لا تريدها من خلاصتك (الجديدة) على Reddit باستخدام التعابير النمطية
// @description:az       (yeni) Reddit lentənizdə istəmədiyiniz yazıları müntəzəm ifadələrlə (regular expressions) süzün
// @description:be       Фільтруйце паведамленні, якія вы не жадаеце бачыць, у вашай (новай) стужцы Reddit з дапамогай рэгулярных выразаў
// @description:bg       Филтрирайте публикации, които не искате, от вашия (нов) Reddit емисия с регулярни изрази
// @description:bn       আপনার (নতুন) Reddit ফিড থেকে নিয়মিত অভিব্যক্তি (regular expressions) ব্যবহার করে এমন পোস্টগুলি ফিল্টার করুন যা আপনি চান না
// @description:bs       Filtrirajte objave koje ne želite iz svoje (nove) Reddit vremenske linije pomoću regularnih izraza
// @description:ca       Filtra les publicacions que no vols del teu feed (nou) de Reddit amb expressions regulars
// @description:cs       Filtrovat příspěvky, které nechcete, ve vašem (novém) Reddit kanálu pomocí regulárních výrazů
// @description:cy       Hidlo bosti nad ydych eisiau eu dileu o'ch ffryd (new) Reddit gan ddefnyddio mynegiadau rheolaidd
// @description:da       Filtrer indlæg, du ikke ønsker, fra din (nye) Reddit-feed med regulære udtryk
// @description:de       Filtere Beiträge, die du nicht willst, aus deinem (neuen) Reddit-Feed mit regulären Ausdrücken
// @description:el       Φιλτράρετε τις δημοσιεύσεις που δεν θέλετε από τη (νέα) ροή Reddit σας με κανονικές εκφράσεις
// @description:es       Filtra las publicaciones que no quieres de tu feed (nuevo) de Reddit con expresiones regulares
// @description:et       Filtreeri postitused, mida sa ei taha, oma (uues) Reddit-voos regulaarsümbolite abil
// @description:fa       پست‌هایی که نمی‌خواهید را از فید (جدید) Reddit خود با عبارات منظم فیلتر کنید
// @description:fi       Suodata pois viestit, joita et halua (uusista) Reddit-syötteestäsi käyttäen säännöllisiä lausekkeita
// @description:fil      Salain ang mga post na ayaw mo mula sa iyong (bagong) Reddit feed gamit ang regular expressions
// @description:fr       Filtrez les publications indésirables de votre flux (nouveau) Reddit avec des expressions régulières
// @description:ga       Scag na poist nach dteastaíonn uait ó do fhotha (nua) Reddit le haistriúcháin rialta
// @description:gl       Filtra as publicacións que non queres do teu feed (novo) de Reddit con expresións regulares
// @description:gu       તમારા (નવા) Reddit ફીડમાંથી નિયમિત અભિવ્યક્તિઓનો ઉપયોગ કરીને તમે ન માંગતા એવા પોસ્ટ્સને ફિલ્ટર કરો
// @description:he       סנן פוסטים שאינך רוצה מהפיד (החדש) שלך ב‑Reddit באמצעות ביטויים רגולריים
// @description:hi       अपने (नए) Reddit फ़ीड से उन पोस्टों को नियमित अभिव्यक्तियों (regular expressions) से फ़िल्टर करें जिन्हें आप नहीं चाहते
// @description:hr       Filtrirajte objave koje ne želite iz svog (novog) Reddit feeda pomoću regularnih izraza
// @description:hu       Szűrd ki a nem kívánt bejegyzéseket az (új) Reddit-hírcsövegedből reguláris kifejezésekkel
// @description:hy       Ֆիլտրեք այն հրապարակումները, որոնք չեք ցանկանում ձեր (նոր) Reddit հոսքից՝ օգտագործելով կանոնավոր արտահայտություններ
// @description:id       Saring postingan yang tidak kamu inginkan dari (baru) feed Reddit-mu dengan ekspresi reguler
// @description:is       Síttu út færslur sem þú vilt ekki úr (nýja) Reddit-fæði með reglulegum segðum
// @description:it       Filtra i post che non vuoi dal tuo feed (nuovo) di Reddit con espressioni regolari
// @description:ja       正規表現を使って、(新しい) Redditフィードから望ましくない投稿をフィルタリングします
// @description:ka       ფილტრავს პოსტებს, якія არ გსურთ თქვენი (ახალი) Reddit ფიდიდან რეგულარული გამოხატულებებით
// @description:kk       (жаңа) Reddit ілмегіңізден қалаусыз жарияланымдарды тұрақты өрнектермен сүзгілеңіз
// @description:km       ប្រាក់ចម្រាញ់បញ្ជីប្រកាសដែលអ្នកមិនចង់បានពីផ្លាទីថ៍ (ថ្មី) Reddit របស់អ្នកដោយប្រើ​ regular expressions
// @description:kn       ನಿಯಮಿತ ಅಭಿವ್ಯಕ್ತಿಗಳನ್ನು ಬಳಸಿ ನಿಮ್ಮ (ಹೊಸ) Reddit ಫೀಡ್‌ನಿಂದ ನೀವು ಇಚ್ಛಿಸದ ಪೋಸ್ಟ್ಗಳನ್ನು ಫಿಲ್ಟರ್ ಮಾಡಿ
// @description:ko       정규 표현식으로 (새) Reddit 피드에서 원하지 않는 게시물 필터링
// @description:ku       Ji hêla hevokên rêzgirtî ve ji feed‑a (nû) Reddit xwe postên ku nîn dixwazin filtre bikin
// @description:lo       ກອກກວດຫົວຂໍ້ທີ່ທ່ານບໍ່ຕ້ອງການອອກຈາກແຟັດ (ໃໝ່) Reddit ຂອງທ່ານໂດຍໃຊ້ຄຳສອບທີ່ສາມາດທໍາຊ້ຳ
// @description:lt       Filtruokite įrašus, kurių nenorite iš savo (naujo) Reddit srauto naudodami reguliarias išraiškas
// @description:lv       Filtrējiet ierakstus, kurus nevēlaties savā (jaunajā) Reddit plūsmā, izmantojot regulārās izteiksmes
// @description:mk       Филтрирајте ги објавите што не ги сакате од вашата (нова) Reddit-стрим со регулярни изрази
// @description:ml       നിങ്ങളുടെ (പുതിയ) Reddit ഫീഡിൽ നിന്ന് നിങ്ങൾക്ക് ആവശ്യമില്ലാത്ത പോസ്റ്റുകൾ തിരിച്ചറിയാനായി റെഗുലർ എക്സ്പ്രെഷനുകൾ ഉപയോഗിച്ച് ഫിൽട്ടർ ചെയ്യുക
// @description:mn       (шинэ) Reddit фийдээс хүсээгүй бичлэгүүдийг тогтмол илэрхийлэлүүдээр шүүж гарга
// @description:mr       आपल्या (नवीन) Reddit फीडमधील तुम्हाला नको असलेले पोस्ट नियमित अभिव्यक्ती वापरून फिल्टर करा
// @description:ms       Tapis pos yang anda tidak mahu dari feed (baru) Reddit anda dengan ekspresi biasa
// @description:mt       Filtra l-postijiet li ma tridx mill-feed (ġdid) ta’ Reddit tiegħek bl-espressjonijiet regolari
// @description:nb       Filtrer innlegg du ikke ønsker fra din (nye) Reddit-feed med regulære uttrykk
// @description:ne       आफ्नो (नयाँ) Reddit फीडबाट तपाईँ नचाहने पोस्टहरू नियमित अभिव्यक्तिहरू प्रयोग गरी फिल्टर गर्नुहोस्
// @description:nl       Filter berichten die je niet wilt uit je (nieuwe) Reddit-feed met reguliere expressies
// @description:nn       Filtrer innlegg du ikkje ønskjer frå din (nye) Reddit‑feed med regulære uttrykk
// @description:or       ନିୟମିତ ଅଭିବ୍ୟକ୍ତିଗୁଡ଼ିକୁ ବ୍ୟବହାର କରି ଆପଣଙ୍କର (ନୂତନ) Reddit ଫିଡ୍‌ରୁ ଆପଣ ଚାହାଁନଥିବା ପୋଷ୍ଟଗୁଡ଼ିକୁ ଫିଲ୍ଟର କରନ୍ତୁ
// @description:pa       ਆਪਣੇ (ਨਵੇਂ) Reddit ਫੀਡ ਤੋਂ ਨਿਯਮਤ ਅਭਿਵ੍ਯਕਤੀਆਂ ਦੀ ਵਰਤੋਂ ਕਰਕੇ ਉਹਨਾਂ ਪੋਸਟਾਂ ਨੂੰ ਫਿਲਟਰ ਕਰੋ ਜੋ ਤੁਸੀਂ ਨਹੀਂ ਚਾਹੁੰਦੇ
// @description:pl       Filtruj posty, których nie chcesz, z twojego (nowego) kanału Reddit przy użyciu wyrażeń regularnych
// @description:ps       د خپل (نوي) Reddit فیډ څخه هغه پوسټونه چې نه یې غواړئ د منظم څرګندونو په کارولو سره فلټر کړئ
// @description:pt       Filtre publicações que não quer do seu feed (novo) do Reddit com expressões regulares
// @description:ro       Filtrează postările pe care nu le dorești din feed‑ul (nou) Reddit folosind expresii regulate
// @description:ru       Фильтруйте посты, которые вы не хотите видеть, в вашей (новой) ленте Reddit с помощью регулярных выражений
// @description:si       ඔබට අවශ්‍ය නැති පෝස්ට් ඔබේ (නව්‍ය) Reddit ෆීඩ් එකෙන් නියමිත ප්‍රකාශ (regular expressions) භාවිතයෙන් විෂ්කම්භ කරන්න
// @description:sk       Filtrovať príspevky, ktoré nechcete, vo vašom (novom) Reddit feede pomocou regulárnych výrazov
// @description:sl       Filtrirajte objave, ki jih ne želite, iz vašega (novega) Reddit vira z regulrnimi izrazi
// @description:sq       Filtroni postimet që nuk i dëshironi nga feed‑i (i ri) Reddit me shprehje të rregullta
// @description:sr       Филтрирајте објаве које не желите из свог (новог) Reddit фида помоћу регуларних израза
// @description:sv       Filtrera inlägg du inte vill ha från din (nya) Reddit‑feed med reguljära uttryck
// @description:sw       Chuja posti ambazo hupendi kutoka kwenye feed yako ya (mpya) Reddit kwa kutumia regex
// @description:ta       உங்கள் (புதிய) Reddit ஊடகப் பகுதியிலிருந்து நீங்கள் விரும்பாத பதிவுகளை নিয়মப் பகுதிகளால் (regular expressions) வடிகட்டவும்
// @description:te       మీ (కొత్త) Reddit ఫీడ్ నుండి మీరు ఇష్టపడని పోస్ట్‌లను నియమిత వ్యక్తీకరణలు ఉపయోగించి ఫిల్టర్ చేయండి
// @description:th       กรองโพสต์ที่คุณไม่ต้องการจากฟีด (ใหม่) ของ Reddit ของคุณด้วยนิพจน์ปกติ
// @description:tl       I‑filter ang mga post na ayaw mo mula sa iyong (bagong) Reddit feed gamit ang regular expressions
// @description:tr       (yeni) Reddit akışınızdan istemediğiniz gönderileri düzenli ifadelerle filtreleyin
// @description:uk       Фільтруйте дописи, яких не хочете, у вашій (новій) стрічці Reddit за допомогою регулярних виразів
// @description:ur       اپنے (نئے) Reddit فیڈ سے وہ پوسٹس فلٹر کریں جو آپ نہیں چاہتے، ریگولر ایکسپریشنز استعمال کرکے
// @description:uz       (yangi) Reddit feed’ingizdan istamagan postlarni muntazam ifodalar bilan filtrlash
// @description:vi       Lọc các bài bạn không muốn từ nguồn (mới) Reddit của bạn bằng biểu thức chính quy
// @description:xh       Hluza iiposti ongafuniyo kwifidi (entsha) yakho yeReddit usebenzisa iirekhweshi eziqhelekileyo
// @description:yi       פֿילטער פּאָסטן וואָס איר טאָן ניט ווילן פֿון דיין (נײַע) Reddit פֿיד מיט רעגולערע אויסדרוקן
// @description:zh-CN    使用正则表达式从你的(新)Reddit 订阅源中过滤你不想要的帖子
// @description:zh-TW    使用正規表達式從你的(新)Reddit 訂閱源中过濾你不想要的貼文
// @name:af              Week Uit Reddit‑plasings
// @name:am              ከReddit ልጥፎች ማስወገድ
// @name:ar              فرز منشورات Reddit
// @name:az              Reddit yazılarını süzün
// @name:be              Адфільтраваць паведамленні Reddit
// @name:bg              Пречисти публикации в Reddit
// @name:bn              Reddit পোস্ট ফিল্টার করুন
// @name:bs              Izdvojite neželjene Reddit objave
// @name:ca              Filtra publicacions de Reddit
// @name:cs              Filtrovat příspěvky Reddit
// @name:cy              Gwahanu postiadau Reddit
// @name:da              Fjern Reddit‑indlæg
// @name:de              Reddit‑Beiträge aussortieren
// @name:el              Φιλτράρισμα δημοσιεύσεων Reddit
// @name:es              Filtrar publicaciones de Reddit
// @name:et              Sorteeri Redditi postitused välja
// @name:fa              پالایش پست‌های Reddit
// @name:fi              Suodata Reddit‑julkaisut
// @name:fil             Salain ang mga post ng Reddit
// @name:fr              Filtrer les publications Reddit
// @name:ga              Scag postanna Reddit
// @name:gl              Filtrar publicacións de Reddit
// @name:gu              Reddit પોસ્ટોને ફિલ્ટર કરો
// @name:he              סינון פוסטים של Reddit
// @name:hi              Reddit पोस्ट फ़िल्टर करें
// @name:hr              Izdvoji neželjene Reddit objave
// @name:hu              Reddit‑bejegyzések kiszűrése
// @name:hy              Reddit գրառումներ ֆիլտրել
// @name:id              Saring postingan Reddit
// @name:is              Sía Reddit‑færslur
// @name:it              Filtra i post di Reddit
// @name:ja              Reddit の投稿をフィルター
// @name:ka              Reddit პოსტების ფილტრი
// @name:kk              Reddit жазбаларын сүзу
// @name:km              ស្វែងយកបដិសេធចេញពី Reddit
// @name:kn              Reddit ಪೋಸ್ಟ್‌ಗಳನ್ನು ಫಿಲ್ಟರ್ ಮಾಡಿ
// @name:ko              Reddit 게시물 필터
// @name:ku              Postên Redditê filtre bike
// @name:lo              ກວດເອົາໂພສ Reddit
// @name:lt              Filtruoti Reddit įrašus
// @name:lv              Filtrēt Reddit ierakstus
// @name:mk              Филтрирај Reddit објави
// @name:ml              Reddit പോസ്റ്റുകൾ ഫിൽറ്റർ ചെയ്യുക
// @name:mn              Reddit постуудыг шүүж гаргах
// @name:mr              Reddit पोस्ट फिल्टर करा
// @name:ms              Tapis siaran Reddit
// @name:mt              Naddaf il‑postijiet taʼ Reddit
// @name:nb              Filtrer Reddit‑innlegg
// @name:ne              Reddit पोस्टहरू फिल्टर गर्नुहोस्
// @name:nl              Reddit‑berichten filteren
// @name:nn              Filtrer Reddit‑innlegg
// @name:or              Reddit ପୋଷ୍ଟଗୁଡିକୁ ଫିଲ୍ଟର କରନ୍ତୁ
// @name:pa              Reddit ਪੋਸਟਾਂ ਫਿਲਟਰ ਕਰੋ
// @name:pl              Filtrowanie postów Reddit
// @name:ps              د Reddit پوستونه فلټر کړئ
// @name:pt              Filtrar publicações do Reddit
// @name:ro              Filtrează postări Reddit
// @name:ru              Фильтровать посты Reddit
// @name:si              Reddit පෝස්ට් ෆිල්ටර් කරන්න
// @name:sk              Filtrovať príspevky Reddit
// @name:sl              Filtriraj Reddit objave
// @name:sq              Filtroni postimet e Reddit
// @name:sr              Филтрирај Reddit постове
// @name:sv              Filtrera Reddit‑inlägg
// @name:sw              Chuja machapisho ya Reddit
// @name:ta              Reddit பதிவுகளை வடிகட்டவும்
// @name:te              Reddit పోస్టులను ఫిల్టర్ చేయండి
// @name:th              กรองโพสต์ Reddit
// @name:tl              I‑filter ang mga post ng Reddit
// @name:tr              Reddit gönderilerini filtrele
// @name:uk              Фільтрувати пости Reddit
// @name:ur              Reddit پوسٹس فلٹر کریں
// @name:uz              Reddit postlarini filtrlash
// @name:vi              Lọc bài viết Reddit
// @name:xh              Cwangcisa izithuba ze‑Reddit
// @name:yi              פילטר זײַטנס Reddit פּאָסטן
// @name:zh-CN           过滤 Reddit 帖子
// @name:zh-TW           過濾 Reddit 帖文
// @author               Jason Melancon
// @license              GNU AGPLv3
// @match                http*://www.reddit.com/*
// @supportURL           https://greatest.deepsurf.us/en/scripts/548300-weed-out-reddit-posts/feedback
// @homepageURL          https://greatest.deepsurf.us/en/scripts/548300-weed-out-reddit-posts
// @grant                GM.getValue
// @grant                GM.setValue
// @grant                GM.deleteValue
// @grant                GM.listValues
// @grant                GM.registerMenuCommand
// @grant                GM.xmlHttpRequest
// @require              https://update.greatest.deepsurf.us/scripts/559642/1722326/Denque-on-Greasy-Fork.js
// @require              https://update.greatest.deepsurf.us/scripts/559799/1722338/Real-Time-Rate-Limiting-Queue.js
// @require              https://update.greatest.deepsurf.us/scripts/562172/1732034/Temporary-Script-Storage.js
// ==/UserScript==

/* jshint esversion: 11 */
/* jshint moz: true */

// Real-Time-Rate-Limiting-Queue library uses Mike Diarmid's Denque (https://github.com/Salakar) — copyright (c) 2018 Invertase Limited (https://github.com/invertase/denque)

(async function() {
    "use strict";

    const DEBUG = false;
    // the msg is in a lambda expression body so that string interpolation only happens if we
    // actually print the message (lazy evaluation)
    function debugLog(lambdifiedMsg, ...args) {
        if (DEBUG) console.log(lambdifiedMsg(...args));
    }

    // Limit background fetches for things like post flair
    const RateLimitQueue = getRtrlqClass();
    const opt = { requests: 10, interval: RateLimitQueue.seconds(10), concurrent: false }; // 60 req/min equivalent
    const requestQueue = new RateLimitQueue(opt.requests, opt.interval, opt.concurrent);

    // Memoize fetched data to obviate re-fetches, but don't keep forever
    const persistentStorage = new TTLStorage();
    await persistentStorage.ready();
    setInterval(() => persistentStorage.sweepExpiredEntries(), 1000 * 60 * 60 * 24);

    /* REMOVE UNWANTED ELEMENTS */

    let regexList = await GM.getValue("regexList", /*default = */[]);
    let logRemovals = await GM.getValue("logRemovals", /*default = */true);
    let namedSubredditLists = {};
    let articles = document.querySelectorAll("article");
    const Target = Object.freeze({ // these are the things the user can currently search within
        Title: "Title", // enum value
        Flair: "Flair"  // enum value
    });

    // try to get named lists of subreddits from options
    function parseNamedSubredditLists(lines) {
        namedSubredditLists = {};
        for (let line of lines) {
            let matches = line.match(/(\w+)\s*=\s*\{\s*(.*?)\s*}\s*$/);
            if (matches) {
                let stringSplit = matches[2].split(/[,;| ]/).map(x => x.trim()).filter(x => !!x);
                namedSubredditLists["_" + matches[1]] = stringSplit;
            }
        }
    }

    // get subreddit list and pattern-target pairs from input line --
    // each pattern is paired with which target property of the post to search in
    // (they all must match), and each line has a list of subreddits it applies to
    //     options lines have these parts: (pattern %=target=%)... {subreddits}
    //     everything is optional; if the pattern is absent, it will be ""
    function parseRegExpLine(line) {
        // already handled by previous parse for named lists
        if (/\s*\w+\s*=\s*{.*}/.test(line)) {
            return [null, null];
        }

        // first, split off the list of subreddits, if present;
        // subreddits list must be separated from the rest by at least one space
        let matches = line.match(/^\s*(?:(.*?)\s+)?\{\s*(.*?)\s*\}\s*$/);
        if (matches) { // subreddit list was found
            var pairsPart = matches[1] ?? "";
            var subredditsPart = matches[2] ?? "";
        } else {
            var pairsPart = line;
            var subredditsPart = "";
        }

        let patternTargetPairs = parsePatternTargetPairs(pairsPart);

        // determine what to search in
        for (let i = 0; i < patternTargetPairs.length; ++i) {
            let target = patternTargetPairs[i][1];
            // get key by value
            let key = Object.keys(Target)
                            .find(key => Target[key].toLowerCase() === target.toLowerCase());
            // default to searching for matching title, if user specified no target or bogus target
            let realTarget = Target[key] ?? Target.Title;

            // substitute corrected target based on what's actually available
            patternTargetPairs[i][1] = realTarget;
        }

        let subredditList = parseSubredditList(subredditsPart);

        return [patternTargetPairs, subredditList];
    }

    // return a list of subreddits
    function parseSubredditList(list) {
        if (list) {
            var subredditList = list.split(/[,;| ]/).map(x => x.trim()).filter(x => !!x);
        } else {
            return [];
        }

        // replace named list with its contents
        let token;
        let subredditListLen = subredditList.length;
        for (let i = 0; i < subredditListLen; i++) {
            token = "_" + subredditList[i];
            if (namedSubredditLists[token]) {
                subredditList.splice(i, 1);
                subredditList.push(...namedSubredditLists[token]);
                // you can't put one named group inside another, so stop
                // before you reach the replaced ones
                i--; subredditListLen--;
            }
        }
        return subredditList;
    }

    // return a list of pattern target pairs
    function parsePatternTargetPairs(ptPairsString, accumList = []) {
        // use recursion
        //
        // if pattern and target are both optional, and this parses a list of pairs of them,
        // how would we know how many pairs there are?
        // answer: only push an empty pair onto the list if the list and string are both empty;
        // the only reason to use more than one pair is if at least one pair has a target specified
        //
        // there's no reason to submit multiple patterns each with no accompanying target, since
        // that would mean both patterns must match in order to have an overall post match, but
        // that can be accomplished with a single pattern; fortunately, with no intervening target
        // group, and no pattern delimiters, there's no way to tell two adjacent patterns apart from
        // one big one anyway
        //
        // the above implies that only one of the pairs can have no target, and it must be the last
        // pair, so that the last two patterns can be separated by a target token
        //
        // no target means the title is the target; no pattern means an empty target is being sought;
        // there's no such thing as a blank title, but if the user really wants to try to find one,
        // that's fine
        //
        // the foregoing means that if you want to look for an empty title (which can't exist) and
        // something else at the same time, you have to specify all targets

        // break off the first pair and leave the rest (the "tail") for the next call
        // (the subreddit list is not part of this string)
        let pattern, target, tail; // (pattern)? %=(target)=% (tail)?
        // pattern and tail are optional and must be separated from the target group by at least one space
        let matches = ptPairsString.match(/^\s*(?:((?!%=).*?(?!=%))\s+)?%=\s*(\w+)\s*=%(?:\s+(\S.*?)?\s*)?$/);
        if (matches) { // target found
            pattern = matches[1] ?? "";
            target = matches[2] ?? "";
            tail = matches[3];
        } else { // no target found, so it's all one big pattern
            pattern = ptPairsString.trim();
            target = tail = "";
        }
        accumList.push([pattern, target]);
        if (tail) {
            return parsePatternTargetPairs(tail, accumList);
        } else return accumList;

        // the only way to have an empty pattern and an empty target is if the tail is also empty,
        // because otherwise what matched the tail would have been picked up by the pattern;
        // and if there's no tail, there's no recursive call; this implies that a blank pattern
        // and target are only possible with an entirely blank input, and cannot but be the only pair
    }

    const BAD_FLAIR_PREFIX = Math.random().toString(36).slice(2);
    const BAD_FLAIR_STATUS = BAD_FLAIR_PREFIX + "_STATUS_";

    // get flair either from the feed card or by loading the post page
    function getPostFlair(post) {
        const postTitle = post.getAttribute("post-title");
        const viewContext = post.getAttribute("view-context") ||
                            console.log(`Post viewing context not listed for "${postTitle}"`);

        function queryFlair(domObj) {
            return Array.from(domObj.querySelectorAll("shreddit-post-flair .flair-content"))
                                    .map(el => el.textContent);
        }

        if (viewContext == "SubredditFeed") { // viewing the post within its own subreddit,
            const flairs = queryFlair(post);  // which is the only way the flair would be on the post already
            return Promise.resolve(flairs);
        }

        let postUrl = post.getAttribute("permalink");

        const executor = (resolve, reject) => {
            GM.xmlHttpRequest({
                method: "GET",
                url: postUrl,
                //synchronous: true,
                headers: {
                    // "User-Agent": "Mozilla/5.0",    // If not specified, navigator.userAgent will be used.
                    // "Accept": "text/xml"            // If not specified, browser defaults will be used.
                },
                onload: function(response) {
                    const status = response.status;

                    debugLog(() => `"${postTitle}" GM.XHR st: ${status}`);
                    if (status < 200 || status > 299) {
                        console.error(`Post "${postTitle}" contains bad "permalink" attribute: ${postUrl}`);
                        // server will still count the request toward the limit, so we must resolve
                        resolve([BAD_FLAIR_STATUS + status]);
                        return;
                    }

                    let responseXML;
                    if (!response.responseXML) {
                        responseXML = new DOMParser().parseFromString(response.responseText, "text/xml");
                    } else {
                        responseXML = response.responseXML;
                    }

                    const flairs = queryFlair(responseXML);
                    resolve(flairs);
                },
                onerror: function(error) {
                    console.error(`Problem fetching "${postTitle}" to get flair:\n${error}`);
                    reject(error); // will not count toward rate limit
                }
            });
        };

        let queueItem = requestQueue.enqueue({ executor: executor });
        return queueItem.then(item => item.promise);
    }

    class StatusError extends Error {
        constructor(message) {
            super(message);
            this.name = "StatusError";
        }
    }

    function flairRetryDecorator(getFlair) {
        return async function(post) {
            let retries = 0;
            let flairList, firstFlair;
            while (retries < 3) {
                if (retries > 0) {
                    console.log(`Retry ${retries}...`)
                    const delay = Math.floor(Math.random() * 500) + 500; // between 0.5 and 1 second
                    await new Promise(r => setTimeout(r, delay));
                }
                try {
                    flairList = await getFlair(post);
                    firstFlair = flairList[0];
                    if (firstFlair?.startsWith(BAD_FLAIR_STATUS)) {
                        const status = firstFlair.slice(BAD_FLAIR_STATUS.length);
                        throw new StatusError("Bad status " + status);
                    }
                    return flairList;
                } catch (err) {
                    if (err instanceof StatusError) throw err;
                    retries++;
                }
            }
            throw new Error(`No more retries; tried ${retries} times`);
        };
    }

    getPostFlair = flairRetryDecorator(getPostFlair);

    // parse lines of regexes, forcing patterns with target="flair" to the end
    // to try to avoid flair comparisons, since those require loading the whole
    // post when looking at the main feed; maybe an earlier target will fail
    // and obviate the need (all targets in a line must match to remove a post)
    function parseAndSortOptionsLines(optionsLines) {
        const parsedLinesList = [];
        optionsLines.forEach(line => {
            const tuple = parseRegExpLine(line);
            if (tuple[0] === null) return; // not a regex line
            const parsedLine = {
                patternTargetPairs: tuple[0],
                subredditList: tuple[1]
            };

            // force pairs with "flair" to the end of the pairs for that line
            function pairCompare(a, b) {
                const targetA = a[1];
                const targetB = b[1];
                if (!targetA && !targetB) return 0;
                if (!targetA && targetB) return -1;
                if (targetA && !targetB) return 1;
                // if (targetA && targetB):
                if (targetA == targetB) return 0;
                if (targetA == Target.Flair) return 1;
                if (targetB == Target.Flair) return -1;
            }
            parsedLine.patternTargetPairs.sort(pairCompare);

            var targetSet = new Set();
            for (let i = parsedLine.patternTargetPairs.length - 1; i >= 0; --i) { // backwards!
                let [pattern, targetEnum] = parsedLine.patternTargetPairs[i];

                // eliminate pairs with bad regex
                let goodRegex = true;
                try {
                    new RegExp(pattern); // validate RegExp
                } catch (_) {
                    goodRegex = false;
                    let err = `[SCRIPT USER ERROR] Invalid regular expression: /${pattern}/`;
                    console.log(err);
                }
                // the user can enter lines with multiple patterns all paired with the same
                // target, which doesn't make sense; therefore, only the lattermost pair with a given
                // target will be kept (first encountered, but this iteration direction is backwards)
                if (!goodRegex || targetSet.has(targetEnum)) {
                    // delete the pair
                    parsedLine.patternTargetPairs.splice(i, 1);
                    if (targetSet.has(targetEnum)) {
                        console.log(`[SCRIPT USER ERROR] Multiple uses of ${targetEnum} target; only using the last one given`);
                    }
                }
                targetSet.add(targetEnum);
            }
            parsedLinesList.push(parsedLine);
        });

        // force lines that have at least one "flair" pair to the end of the list of options lines,
        // so that maybe a previous line will remove the post and flair doesn't have to be checked
        function lineCompare(a, b) {
            const targetA = a.patternTargetPairs.some(pair => pair[1] == Target.Flair);
            const targetB = b.patternTargetPairs.some(pair => pair[1] == Target.Flair);
            if (targetA == targetB) return 0;
            if (!targetA && targetB) return -1;
            if (targetA && !targetB) return 1;
        }
        return parsedLinesList.sort(lineCompare);
    }

    async function removeArticles(articles, optionsLines) {
        const parsedLinesList = parseAndSortOptionsLines(optionsLines);
        const ABBREV_LENGTH = 20;

        for (let i = 0; i < articles.length; i++) {
            // these things don't change for a given article
            const post = articles[i].querySelector("shreddit-post");
            const postId = post.getAttribute("id");
            const postTitle = post.getAttribute("post-title");
            const subreddit = post.getAttribute("subreddit-name") ??        // posts to a followed u/user have no true r/subreddit,
                              post.getAttribute("subreddit-prefixed-name"); // but they have this string beginning with "u_"
            let flairList, flairListSanitized;

            let deletePost = false;
            for (let line of parsedLinesList) {

                // before anything else, check that the post's subreddit is in the provided subreddit list
                if (line.subredditList.length > 0) {
                    if (!line.subredditList.map(x => x.toLowerCase()).includes(subreddit.toLowerCase())) {
                        debugLog(() => `article ${i}: "${postTitle.substring(0, ABBREV_LENGTH)
                                       }...": r/${subreddit} not among ` + line.subredditList.map(x => "r/" + x).join(", "))
                        continue; // to next line; subreddit list doesn't include this post's subreddit
                    }
                }

                // there may be many things the user wants to match before removing a post,
                // and they all must be tested in a big logical conjunction
                deletePost = true;
                let currentPairMatch;
                const targetSet = new Set();
                for (let [pattern, target] of line.patternTargetPairs) {
                    currentPairMatch = false;
                    targetSet.add(target);
                    let targetText = "";
                    switch (target) {
                        case Target.Flair:
                            // this is complicated by the fact that Reddit posts can have
                            //   - no flair
                            //   - empty flair
                            //   - multiple flairs, any of which can be empty

                            if (flairList === undefined) {
                                // apparently, flairs are only put on posts in their subreddit of origin,
                                // so if the post is in its subreddit, get the flair from the article, and
                                // if the post is in the Reddit feed (i.e., on the home page), try to
                                // slyly load the post and get the flair, but only do it once per post
                                if (persistentStorage.has(postId)) {
                                    flairList = persistentStorage.get(postId);
                                    debugLog(() => `Persistent storage: ${postId} -> ${flairList.map(f => f.trim()).join(", ")}`);
                                } else {
                                    try {
                                        flairList = await getPostFlair(post);
                                    } catch (err) {
                                        console.error(err);
                                        currentPairMatch = false; // no match possible on error
                                        targetText = err.name;
                                        break;
                                    }
                                    persistentStorage.set(postId, flairList); // stored for limited time
                                }
                                if (!flairList.length) debugLog(() => `article ${i}: Empty flair for "${postTitle}"`);
                            }

                            // if the pattern is length 0 and the post has no flair,
                            // remove the post (this is the only way to remove posts with no flair)
                            if (flairList.length === 0 && pattern.length === 0) {
                                targetText = "";
                                currentPairMatch = true;
                                break;
                            }
                            // get rid of all empty flair (including strange unprintable things)
                            if (flairListSanitized === undefined) {
                                flairListSanitized = flairList.map(f => f.trim())
                                .filter(f => !f.match(/^[^a-zA-Z0-9!@#%&\$\^\*\(\)\[\]\{\}\?\.;,\+\-\\\/':"`~<>]*$/));
                            }

                            // if the flairs are all empty and the pattern matches an empty string,
                            // remove the post
                            if (flairListSanitized.length === 0 && "".match(pattern)) {
                                targetText = "";
                                currentPairMatch = true;
                                break;
                            }
                            // from here onward, an empty pattern isn't helpful
                            if (pattern.length === 0) {
                                break;
                            }
                            // if there is at least one non-empty flair that matches the non-empty pattern,
                            // remove the post
                            for (let j = 0; j < flairListSanitized.length; ++j) {
                                if (flairListSanitized[j].match(pattern)) {
                                    targetText = flairListSanitized[j];
                                    currentPairMatch = true;
                                    break;
                                }
                            }
                            targetText = flairListSanitized.join(",");
                            break;
                        case Target.Title:
                        default:
                            targetText = postTitle;
                            if (pattern && postTitle.match(pattern) ||
                                !pattern && postTitle.trim().length === 0)
                            {
                                currentPairMatch = true;
                            }
                            break;
                    }
                    debugLog(() => `Testing ${target.toLowerCase()} (${targetText}) vs. ${pattern}: ${currentPairMatch}`); // DEBUG

                    // in order to remove a post, all patterns in the line must match their targets,
                    // so as soon as a pattern fails to match, continue to next options line
                    if (!currentPairMatch) {
                        deletePost = false;
                        break; // out of pairs loop
                    }
                }
                debugLog(() => `article ${i}: ${postTitle}|${line.patternTargetPairs}|${flairListSanitized}|{${line.subredditList}}`); // DEBUG
                if (!deletePost) continue; // to next options line

                const hr = articles[i].nextElementSibling;
                if (hr && hr.tagName == "HR") {
                    hr.remove();
                }
                articles[i].remove();
                if (logRemovals || DEBUG) {
                    let flairs = (targetSet.has(Target.Flair)) ? ` (flair:${flairListSanitized.join(", ")})` : "";
                    console.log(`Userscript removed "${postTitle}"${flairs} in r/${subreddit}`);
                }
                break; // it's certain that this line removes this article, so skip to next article
            }
            if (!deletePost) {
                debugLog(() => `article ${i}: "${ postTitle.substring(0, ABBREV_LENGTH)
                                                }..." not removed: No matching line of patterns`); // DEBUG
            }
        }
    }

    // get named lists of subreddits
    parseNamedSubredditLists(regexList);

    // remove articles from initial page load, before scrolling
    removeArticles(articles, regexList); // async

    // remove articles that appear when scrolling
    new MutationObserver(async mutationList => {
        for (let mutation of mutationList) {
            if (mutation.type == "childList") {
                const additions = Array.from(mutation.addedNodes);
                articles = additions.reduce((accumulator, currentNode) => {
                    // added nodes could be articles, elements that contain articles, or neither
                    if (currentNode.nodeType === Node.ELEMENT_NODE) {
                        if (currentNode.tagName === "ARTICLE") {
                            return accumulator.concat(currentNode); // added node is article
                        }
                        const containedArticles = Array.from(currentNode.querySelectorAll("article"));
                        return accumulator.concat(containedArticles); // added node has possible descendent articles
                    }
                    return accumulator; // added node is not an element
                }, []);
                if (articles.length == 0) {
                    continue;
                }
                debugLog(() => `${articles.length} new articles`); // DEBUG

                // make local copy of articles list, since execution leaves this function
                // at "await" and something happens to the list before execution resumes
                const localArticlesCopy = Array.from(articles);

                // refresh in case user updated options in the meantime
                regexList = await GM.getValue("regexList", /*default = */[]);
                logRemovals = await GM.getValue("logRemovals", /*default = */true);
                parseNamedSubredditLists(regexList);
                await removeArticles(localArticlesCopy, regexList); // async
            }
        }
    }).observe(document.body, { childList: true, subtree: true });

    /* SET SCRIPT OPTIONS */

    // create the options page
    const optionsHtml = `
        <!DOCTYPE html>
        <html>
        <head>
            <title>Script Options</title>
            <style>
                #options {
                    /* for some reason this is required for checkbox alignment */
                }
                #options label {
                    all: unset;
                    font-size: 9pt;
                }
                #options label[for="regexList"] {
                    display: block;
                    margin-bottom: 10px;
                }
                #options textarea {
                    background-color: black;
                    display: block;
                    margin-bottom: 5px;
                    font-size: 9pt;
                    font-family: 'Lucida Console', Monaco, monospace;
                }
                #options button {
                    margin-top: 10px;
                    border-radius: 4px;
                    padding-left: 10px;
                    padding-right: 10px;
                }
                #options input[type="checkbox"],
                #options input[type="checkbox"] + label {
                    margin-top: 12px;
                    display: inline-block;
                }
                #options input[type="checkbox"] {
                    margin-left: 0px;
                    position: relative;
                    top: -6px;
                }
                #options p {
                    line-height: initial;
                    font-size: 8pt;
                    margin-top: 5pt;
                    margin-bottom: 5pt;
                }
                #options p#note {
                    color: color-mix(in srgb, currentColor, red 20%);
                }
                #options p > span {
                    font-family: 'Lucida Console', Monaco, monospace;
                }
                #options p > span#jokes {
                    font-family: unset;
                    white-space: nowrap;
                }
                #options form div {
                    max-width: 350px;
                    box-sizing: border-box;
                }
                #options div:has( > code) {
                    line-height: initial;
                    background-color: black;
                }
                #options code {
                    all: unset;
                    font-size: 8pt;
                    font-family: 'Lucida Console', Monaco, monospace;
                    color: inherit;
                    background-color: inherit;
                    border: 0px;
                }
            </style>
        </head>
        <body>
            <div id="options">
                <h1>Script Options</h1>
                <form id="optionsForm">
                    <label for="regexList">
                        Posts will be hidden if title matches one of these <a><strong>reg</strong>ular <strong>ex</strong>pressions</a>:
                    </label>
                    <textarea id="regexList" name="regexList" rows="5" cols="33" spellcheck="false"></textarea>
                    <div>
                        <p>You can follow a <a><strong>regex</strong></a> with a list of subreddits in curly braces. In that case,
                            the pattern will only be used to remove posts from those subreddits.</p>
                        <p>Not only that, but you can add lines that create named lists of subreddits, and then put
                            these names after a regex in place of the list they represent, like so:</p>
                        <div>
                            <code>favorites = { funny, politics }<br>
                                  [tT]rump { favorites, rant }</code>
                        </div>
                        <p>If you'd rather search in something other than the post title, enclose the alternative search target like
                            <span>%= this =%</span> after the regex but before any list of subreddits. Currently, the target can either be
                            <span>title</span> or <span>flair</span>. The following example removes all jokes except ones with "long" flair in
                            <span id="jokes">r/jokes:</span></p>
                        <div>
                            <code>^(?!\\s*[Ll]ong\\s*$)(?!\\s*$).+ %= flair=% {jokes}<br>
                                  %= flair<wbr>&nbsp;<wbr>&nbsp;<wbr>=%<wbr>&nbsp;<wbr>&nbsp;<wbr>&nbsp;<wbr>{ jokes }</code>
                        </div>
                        <p>The second line above takes care of removing posts with no flair at all.</p>
                        <p>Each line can have one regex pattern for each possible search target. A line with multiple targets requires
                            that all patterns match their targets in order to remove a post. If a pattern has no target following it,
                            it is assumed to be targeting the title. Separate targets and patterns from each other and from subreddit lists
                            by a space.</p>
                        <p>The following example removes posts about football stadiums:</p>
                        <div>
                            <code>[Ff]ootball %= flair =% [Ss]tadium { sports }</code>
                        </div>
                        <p id="note">Note: Do not enclose your regex in <span>/slashes/</span> unless the slashes are part of the search!</p>
                    </div>
                    <input id="logCheckbox" name="logCheckbox" type="checkbox">
                    <label for="logCheckbox">
                        Log filtered posts to the Developer Tools console
                    </label>
                    <div>
                        <button type="submit">Save</button>
                        <button id="closeOptions">Close</button>
                    </div>
                </form>
            <div>
        </body>
        </html>
    `;

    async function openOptionsInterface() {
        // create a modal for the options interface. Use an in-page modal because
        // - it doesn't use GM_openInTab because Firefox doesn't allow data: URLs,
        //   so the HTML would have to be in a separate file
        // - it doesn't use a separate HTML file, because I have no idea how to install
        //   that along with a userscript, and the userscript can't generate one
        // - it doesn't use a popup window, because those are typically blocked on a
        //   per-site basis by the browser settings
        const modal = document.createElement("div");
        modal.style.position = "fixed";
        modal.style.top = "0";
        modal.style.left = "0";
        modal.style.width = "100%";
        modal.style.height = "100%";
        modal.style.backgroundColor = "rgba(0, 0, 0, 0.5)";
        modal.style.zIndex = "9999";
        modal.style.display = "flex";
        modal.style.justifyContent = "center";
        modal.style.alignItems = "center";

        const scrollBox = document.createElement("div");
        scrollBox.style.maxHeight = "100vh";
        scrollBox.style.overflowY = "auto";
        scrollBox.style.scrollbarGutter = "stable";
        scrollBox.style.padding = "0px";
        scrollBox.style.border = "0px";
        scrollBox.style.margin = "0px";

        const optionsBox = document.createElement("div");
        optionsBox.id = "options";
        optionsBox.style.backgroundColor = "hsl(from thistle h s calc(l - .90*l))";
        optionsBox.style.padding = "20px";
        optionsBox.style.borderRadius = "5px";
        optionsBox.style.boxShadow = "0 0 10px rgba(0, 0, 0, 0.8)";
        optionsBox.innerHTML = optionsHtml;

        // fill text entry with saved value, if any
        const regexArea = optionsBox.querySelector("textarea");
        regexArea.value = (await GM.getValue("regexList", /*default = */[])).join("\n");
        // place text entry cursor
        if (typeof regexArea.setSelectionRange === "function") {
            regexArea.focus();
            regexArea.setSelectionRange(0, 0);
        } else if (typeof regexArea.createTextRange === "function") {
            const range = regexArea.createTextRange();
            range.moveStart('character', 0);
            range.select();
        }

        // set checkbox to saved value (defaults to checked)
        const logCheckbox = optionsBox.querySelector("input#logCheckbox");
        logCheckbox.checked = await GM.getValue("logRemovals", /*default = */true);

        // set up explanatory links about regular expressions
        const regexLinks = optionsBox.querySelectorAll("a");
        regexLinks.forEach(a => {
            a.href = "https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_expressions";
            a.target = "_blank";
            a.style.color = "inherit";
        });

        modal.appendChild(scrollBox);
        scrollBox.appendChild(optionsBox);
        document.body.appendChild(modal);

        regexArea.focus();

        // set up example text style
        optionsBox.querySelectorAll("#options div:has( > code)").forEach(el => {
            el.style.width = "100%";
            el.style.padding = "10px";
            el.style.paddingTop = "3px";
            el.style.paddingBottom = "6px";
        });

        // add button event listeners to set handlers
        // (button listeners are removed when the modal is removed/closed)
        function addButtonHandlers() {
            const form = document.getElementById("optionsForm");
            if (form) {
                // handle form submission (save options)
                form.addEventListener("submit", async function handleFormSubmit(event) {
                    event.preventDefault();
                    let newRegexList = document.getElementById("regexList").value.split("\n");
                    newRegexList = newRegexList.filter(item => item.trim() !== "");
                    await GM.setValue("regexList", newRegexList);
                    await GM.setValue("logRemovals", logCheckbox.checked);
                    alert("Options saved!");
                });
                // close modal
                document.getElementById("closeOptions").addEventListener("click", async function() {
                    document.body.removeChild(modal);
                    // update display using new settings
                    regexList = await GM.getValue("regexList", /*default = */[]);
                    logRemovals = await GM.getValue("logRemovals", /*default = */true);
                    parseNamedSubredditLists(regexList);
                    await removeArticles(articles, regexList); // async
                });
            }
        }

        // decide when to add form's event listeners
        if (document.readyState === "loading") {
            // loading hasn't finished yet
            document.addEventListener("DOMContentLoaded", addButtonHandlers, { once: true });
        } else {
            // DOMContentLoaded has already fired
            addButtonHandlers();
        }
    }

    // set the options handler
    GM.registerMenuCommand("Options", openOptionsInterface);

})();