Copy LaTeX formulas when copying text on Zhihu, Wikipedia, OpenReview and ChatGPT.
// ==UserScript==
// @name FormulaCopier
// @namespace http://tampermonkey.net/
// @license MIT
// @version 0.5.1
// @description Copy LaTeX formulas when copying text on Zhihu, Wikipedia, OpenReview and ChatGPT.
// @author Yuhang Chen(github.com/yuhangchen0), Dramwig(github.com/Dramwig)
// @match https://www.zhihu.com/*
// @match https://zhuanlan.zhihu.com/p/*
// @match https://*.wikipedia.org/*
// @match https://openreview.net/*
// @match https://chatgpt.com/*
// @grant none
// ==/UserScript==
(function() {
'use strict';
document.addEventListener('copy', function(event) {
// ⭐ ChatGPT 特殊处理：复制前先把 LaTeX 写到 data-latex 上
if (window.location.hostname.includes('chatgpt.com')) {
cacheChatGPTLatex();
}
let selectedHtml = getSelectionHtml();
if (window.location.hostname.includes('zhihu.com')) {
handleZhihu(selectedHtml, event);
} else if (window.location.hostname.includes('wikipedia.org')) {
handleWiki(selectedHtml, event);
} else if (window.location.hostname.includes('openreview.net')) {
handleOpenReview(selectedHtml, event);
} else if (window.location.hostname.includes('chatgpt.com')) {
handleChatGPT(selectedHtml, event);
}
});
document.addEventListener('selectionchange', function() {
let formulaSelector = null;
if (window.location.hostname.includes('zhihu.com')) {
formulaSelector = '.ztext-math';
} else if (window.location.hostname.includes('wikipedia.org')) {
formulaSelector = '.mwe-math-element';
} else if (window.location.hostname.includes('openreview.net')) {
formulaSelector = 'mjx-container';
} else if (window.location.hostname.includes('chatgpt.com')) {
formulaSelector = '.katex';
}
if (!formulaSelector) {
return;
}
const allFormulas = document.querySelectorAll(formulaSelector);
allFormulas.forEach(removeHighlightStyle);
const sel = window.getSelection();
if (!sel.rangeCount) {
return;
}
for (let i = 0; i < sel.rangeCount; i++) {
const range = sel.getRangeAt(i);
allFormulas.forEach(formula => {
if (range.intersectsNode(formula)) {
applyHighlightStyle(formula);
}
});
}
});
function cacheChatGPTLatex() {
const formulas = document.querySelectorAll('.katex');
formulas.forEach(formula => {
if (!formula.hasAttribute('data-latex')) {
const annotation = formula.querySelector('annotation[encoding="application/x-tex"]');
if (annotation) {
formula.setAttribute('data-latex', annotation.textContent.trim());
}
}
});
}
function handleZhihu(selectedHtml, event) {
if (selectedHtml.includes('data-tex')) {
const container = document.createElement('div');
container.innerHTML = selectedHtml;
replaceZhihuFormulas(container);
setClipboardData(event, container.textContent);
}
}
function handleWiki(selectedHtml, event) {
if (selectedHtml.includes('mwe-math-element')) {
const container = document.createElement('div');
container.innerHTML = selectedHtml;
replaceWikipediaFormulas(container);
setClipboardData(event, container.textContent);
}
}
function handleOpenReview(selectedHtml, event) {
if (selectedHtml.includes('mjx-container')) {
const container = document.createElement('div');
container.innerHTML = selectedHtml;
replaceOpenReviewFormulas(container);
setClipboardData(event, container.textContent);
}
}
function handleChatGPT(selectedHtml, event) {
if (selectedHtml.includes('katex')) {
const container = document.createElement('div');
container.innerHTML = selectedHtml;
replaceChatGPTFormulas(container);
setClipboardData(event, container.textContent);
}
}
function applyHighlightStyle(formula) {
const mathJaxSVG = formula.querySelector('.MathJax_SVG');
if (mathJaxSVG && mathJaxSVG.style) {
mathJaxSVG.style.backgroundColor = 'lightblue';
return;
}
const mathJaxCHTML = formula.querySelector('mjx-math');
if (mathJaxCHTML && mathJaxCHTML.style) {
mathJaxCHTML.style.backgroundColor = 'lightblue';
return;
}
const katexHtml = formula.querySelector('.katex-html');
if (katexHtml && katexHtml.style) {
katexHtml.style.backgroundColor = 'lightblue';
return;
}
if (formula && formula.style) {
formula.style.backgroundColor = 'lightblue';
}
}
function removeHighlightStyle(formula) {
const mathJaxSVG = formula.querySelector('.MathJax_SVG');
if (mathJaxSVG && mathJaxSVG.style) {
mathJaxSVG.style.backgroundColor = '';
}
const mathJaxCHTML = formula.querySelector('mjx-math');
if (mathJaxCHTML && mathJaxCHTML.style) {
mathJaxCHTML.style.backgroundColor = '';
}
const katexHtml = formula.querySelector('.katex-html');
if (katexHtml && katexHtml.style) {
katexHtml.style.backgroundColor = '';
}
if (formula && formula.style) {
formula.style.backgroundColor = '';
}
}
function getLatexFromMjxContainer(container) {
if (!window.MathJax?.startup?.document) return null;
const counter = container.getAttribute('ctxtmenu_counter');
const target = counter
? document.querySelector(`mjx-container[ctxtmenu_counter="${counter}"]`) || container
: container;
const mathItems = MathJax.startup.document.getMathItemsWithin(target);
const math = mathItems[0]?.math;
return typeof math === 'string' ? math.trim() : null;
}
function replaceOpenReviewFormulas(container) {
container.querySelectorAll('mjx-container').forEach(formula => {
const texCode = getLatexFromMjxContainer(formula);
if (texCode) {
formula.replaceWith(document.createTextNode('$' + texCode + '$'));
}
});
}
function replaceWikipediaFormulas(container) {
const formulas = container.querySelectorAll('.mwe-math-element');
formulas.forEach(formula => {
const annotation = formula.querySelector('annotation[encoding="application/x-tex"]');
if (annotation) {
const texCode = annotation.textContent;
const texNode = document.createTextNode('$' + texCode + '$');
formula.replaceWith(texNode);
}
});
}
function replaceChatGPTFormulas(container) {
container.querySelectorAll('.katex').forEach(formula => {
// ⭐ 优先使用复制前缓存好的 data-latex
let texCode = formula.getAttribute('data-latex');
// 兼容：如果选区里恰好带了 annotation，也可以直接用
if (!texCode) {
const annotation = formula.querySelector('annotation[encoding="application/x-tex"]');
if (annotation) {
texCode = annotation.textContent.trim();
}
}
if (texCode) {
formula.replaceWith(document.createTextNode('$' + texCode + '$'));
}
// 如果依然拿不到 texCode，就不动这个节点，退回原生复制行为
});
}
function replaceZhihuFormulas(container) {
const formulas = container.querySelectorAll('.ztext-math');
formulas.forEach(formula => {
const texCode = formula.getAttribute('data-tex');
const texNode = document.createTextNode('$' + texCode + '$');
formula.replaceWith(texNode);
});
}
function setClipboardData(event, text) {
event.clipboardData.setData('text/plain', text);
event.preventDefault();
}
function convertLineBreaks(node) {
if (node.nodeName === 'BR') {
node.parentNode.replaceChild(document.createTextNode('\n'), node);
} else if (node.nodeName === 'P' && node.nextElementSibling) {
// Add a newline after the section
node.appendChild(document.createTextNode('\n\n'));
} else {
const children = Array.from(node.childNodes);
for (let child of children) {
convertLineBreaks(child);
}
}
}
function getSelectionHtml() {
const sel = window.getSelection();
if (sel.rangeCount) {
const container = document.createElement('div');
for (let i = 0, len = sel.rangeCount; i < len; ++i) {
container.appendChild(sel.getRangeAt(i).cloneContents());
}
// Keep newline
convertLineBreaks(container);
return container.innerHTML;
}
return '';
}
})();