Press 'H' to highlight selected text. Press 'H' again on highlighted text to remove it.
As of
// ==UserScript==
// @name Highlight selected text
// @namespace https://greasyfork.org
// @version 1.0
// @description Press 'H' to highlight selected text. Press 'H' again on highlighted text to remove it.
// @author Bui Quoc Dung
// @match *://*/*
// @grant GM_addStyle
// ==/UserScript==
(function() {
'use strict';
GM_addStyle(`
mark.userscript-highlight {
background-color: #fff59d !important;
color: black !important;
}
`);
document.addEventListener('keydown', function(e) {
if (e.key.toLowerCase() !== 'h') return;
if (e.target.isContentEditable || ['INPUT', 'TEXTAREA'].includes(e.target.tagName)) return;
const selection = window.getSelection();
if (!selection.rangeCount || selection.isCollapsed) return;
e.preventDefault();
const range = selection.getRangeAt(0);
const existingMark = range.commonAncestorContainer.parentElement.closest('mark.userscript-highlight');
if (existingMark) {
const parent = existingMark.parentNode;
while (existingMark.firstChild) {
parent.insertBefore(existingMark.firstChild, existingMark);
}
parent.removeChild(existingMark);
parent.normalize();
} else {
const mark = document.createElement("mark");
mark.className = 'userscript-highlight';
try {
range.surroundContents(mark);
} catch (error) {
console.error("Highlighting failed", error);
alert("Unable to highlight this selection. Please try selecting a simpler text region.");
}
}
selection.removeAllRanges();
});
})();