Page Text Highlighter

WHAT IT DOES This tool lets you highlight any text on any webpage with a persistent background color. Enter a word or phrase, and the tool finds all matches on the page, wraps them in a colored highlight, and optionally scrolls to the first match. You can customize the highlight color, toggle case-sensitive matching, and choose whether to auto-scroll. Highlights are temporary—they affect only your view of the page and are removed when you clear them or close the panel. The tool works on static pages, single-page apps, and dynamically loaded content. WHERE IT RUNS Runs on any website—articles, documentation, forums, dashboards, or any page with text content. It works across all text nodes, skipping script, style, and noscript tags. No per-site configuration needed; the tool automatically scans the entire page for your search term. HOW TO USE Install the userscript via BotGentz, then open the panel and type the text you want to highlight into the input field. Click "Highlight" or press Enter to apply the highlights. Use "Clear Highlights" to remove all highlights. Customize the highlight color using the color picker—the color updates in real-time for existing and future highlights. Toggle case sensitivity, auto-scroll, and whether highlights should persist across page navigation in the settings section. Use the keyboard shortcut Ctrl+Shift+H to quickly focus the input field. TECHNICAL MECHANISM The tool uses a TreeWalker to traverse all text nodes in the document, skipping script, style, and noscript tags, as well as its own highlight marks. It builds a regular expression from the search term, escaping special characters, and applies it case-sensitively or case-insensitively based on the setting. For each match, it splits the text node and wraps the matched portion in a with a CSS class that applies the highlight color. The original text node is replaced with a document fragment containing alternating text nodes and highlight spans. This approach preserves the DOM structure and allows the highlights to be removed by simply replacing each highlight span with its text content. For single-page apps, a MutationObserver monitors URL changes and re-applies highlights if the preserve-on-navigation setting is enabled. THE PANEL The floating panel is built with BotGentz's BGPanel framework. It is draggable—click and drag the panel header to reposition it anywhere on the screen. The panel remembers its position per site via the settings dropdown. It can be collapsed to a small bubble icon by clicking the minimize button, preserving screen space. The panel can be closed and reopened via the BotGentz toolbar. Press the Escape key to quickly close the panel. The panel automatically adjusts its layout for different screen sizes. PLEASE NOTE Requires the free BotGentz extension. This tool processes text entirely in your browser and does not send any data to external servers. Highlights are temporary and do not modify the underlying page content—they are removed when the panel is closed or when you clear them. Websites change frequently; if the tool stops working on a particular site, the script may need updating. Settings are saved locally via GM_setValue and persist across page reloads. The tool cannot highlight text inside password, hidden, or file input fields.