// ==UserScript==
// @name Weed Out Reddit Posts
// @namespace github.com/JasonAMelancon
// @version 2025-09-06
// @description Remove unwanted posts from (new) Reddit
// @author Jason Melancon
// @license GNU AGPLv3
// @match http*://www.reddit.com/*
// @grant GM_getValue
// @grant GM_setValue
// @grant GM_registerMenuCommand
// ==/UserScript==
(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) {
if (DEBUG) console.log(lambdifiedMsg());
}
/* REMOVE UNWANTED ELEMENTS */
let regexList = GM_getValue("regexList", /*default = */[]);
let logRemovals = GM_getValue("logRemovals", /*default = */true);
let namedSubredditLists = {};
let subredditList = []; // parsed anew each line of options; restricts post removal to these subreddits
let articles = document.querySelectorAll("article");
const Target = Object.freeze({
Title: "Title", // enum value
Flair: "Flair" // enum value
});
// try to get named lists of subreddits from options
function parseSubredditLists(lines) {
for (let line of lines) {
let matches = [];
if (matches = line.match(/(\w+)\s*=\s*\{\s*(.*?)\s*}\s*$/)) {
let stringSplit = matches[2].split(/[,;| ]/).map(x => x.trim()).filter(x => !!x);
namedSubredditLists["_" + matches[1]] = stringSplit;
}
}
}
// get pattern, intended search target, and subreddit list --
// assemble list of subreddits to use with the current RegExp in options
// options lines have three parts: /pattern/ %= target =% { subreddits }
// everything is optional; if the pattern is absent, it will be ""
function parseRegExpLine(line) {
// already handled by previous parse for named lists
if (/\w+\s*=\s*{.*}/.test(line)) {
return [null, null];
}
let matches, pattern, target, intendedTarget, list;
if (matches = line.match(/^\s*(.*?)(?:\s*%=\s*(\w+)\s*=%\s*)?(?:\s+{\s*(.*?)\s*})?\s*$/)) {
pattern = matches[1] ?? "";
intendedTarget = matches[2];
list = matches[3];
// determine what to search in -- currently, title (default) or flair
target = Target.Title; // search for matching title by default
if (intendedTarget) {
// get key by value
let key = Object.keys(Target)
.find(key => Target[key].toLowerCase() === intendedTarget.toLowerCase());
target = Target[key] ?? Target.Title; // default again if user specified bogus target
}
// split list
if (list) {
subredditList = list.split(/[,;| ]/).map(x => x.trim()).filter(x => !!x);
debugLog(() => `sub list = ${list}`); // DEBUG
} else {
debugLog(() => "emptying subredditList"); // DEBUG
subredditList = [];
}
// 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 [pattern, target];
}
function removeArticles(articles, optionsLines) {
for (let i = 0; i < articles.length; i++) {
let target, pattern;
for (let line of optionsLines) {
[pattern, target] = parseRegExpLine(line);
if (pattern === null) continue; // not a regex line
try {
new RegExp(pattern); // validate RegExp
} catch (_) {
let err = `Invalid RegExp: ${pattern}`;
console.log(err);
alert(err);
return;
}
let postTitle = articles[i].getAttribute("aria-label");
let flairList = [];
let targetText = "";
let deletePost = false;
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
flairList = Array.from(articles[i].querySelectorAll(".flair-content")).map(el => el.textContent);
// 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 = "";
deletePost = true;
break;
}
// get rid of all empty flair (including strange unprintable things)
flairList = 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 (flairList.length === 0 && "".match(pattern)) {
targetText = "";
deletePost = 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 < flairList.length; ++j) {
if (flairList[j].match(pattern)) {
targetText = flairList[j];
deletePost = true;
break;
}
}
break;
case Target.Title:
default:
if (pattern && postTitle.match(pattern)) {
targetText = postTitle;
deletePost = true;
}
break;
}
debugLog(() => `article ${i}: ${postTitle}|${pattern}|${flairList}|{${subredditList}}`); // DEBUG
if (!deletePost) continue;
debugLog(() => `Match! ${targetText} == ${pattern}`); // DEBUG
let subreddit = articles[i].querySelector("shreddit-post").getAttribute("subreddit-name");
if (subredditList.length > 0) {
if (!subredditList.map(x => x.toLowerCase()).includes(subreddit.toLowerCase())) {
debugLog(() => `Not removed: sub = ${subreddit}`) // DEBUG
continue; // subreddit list doesn't include this post's subreddit
}
}
const hr = articles[i].nextElementSibling;
if (hr && hr.tagName == "HR") {
hr.remove();
}
articles[i].remove();
if (logRemovals) {
let flairs = (target === Target.Flair) ? ` (flair:${flairList.join(", ")})` : "";
console.log(`Userscript removed "${postTitle}"${flairs} in r/${subreddit}`);
}
break;
}
}
}
// get named lists of subreddits
parseSubredditLists(regexList);
// remove articles from initial page load, before scrolling
removeArticles(articles, regexList);
// remove articles that appear when scrolling
new MutationObserver(mutationList => {
debugLog(() => `${mutationList.length} new mutations`); // DEBUG
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
}, []);
debugLog(() => `${articles.length} new articles`); // DEBUG
if (articles.length == 0) {
continue;
}
regexList = GM_getValue("regexList", /*default = */[]); // refresh in case user updated options
removeArticles(articles, regexList);
}
}
}).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> <wbr> <wbr>=%<wbr> <wbr> <wbr> <wbr>{ jokes }</code>
</div>
<p>The second line above takes care of removing posts with no flair at all.</p>
<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 removed items to the Developer Tools console
</label>
<div>
<button type="submit">Save</button>
<button id="closeOptions">Close</button>
</div>
</form>
<div>
</body>
</html>
`;
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 = 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 = 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", function handleFormSubmit(event) {
event.preventDefault();
let newRegexList = document.getElementById("regexList").value.split("\n");
newRegexList = newRegexList.filter(item => item.trim() !== "");
GM_setValue("regexList", newRegexList);
GM_setValue("logRemovals", logCheckbox.checked);
alert("Options saved!");
});
// close modal
document.getElementById("closeOptions").addEventListener("click", function() {
document.body.removeChild(modal);
// update display using new settings
regexList = GM_getValue("regexList", /*default = */[]);
logRemovals = GM_getValue("logRemovals", /*default = */true);
parseSubredditLists(regexList);
removeArticles(articles, regexList);
});
}
// opening options adds this new listener every time, so remove every time
document.removeEventListener("DOMContentLoaded", addButtonHandlers);
}
// decide when to add form's event listeners
if (document.readyState === "loading") {
// loading hasn't finished yet
document.addEventListener("DOMContentLoaded", addButtonHandlers);
} else {
// DOMContentLoaded has already fired
addButtonHandlers();
}
}
// set the options handler
GM_registerMenuCommand("Options", openOptionsInterface);
})();
