Until approximately 2017, the Google product forums allowed styling posts with underline, text color and size, and text background color, perhaps also font type, implemented through a JavaScript-based WISIWYG rich text editor.

In ~2017, their text editor was stripped of most functionality, and custom colours and font sizes were removed from existing posts.

Does anyone have the JavaScript code of that legacy rich text editor? If anyone has downloaded a page from Google product forums back then, the JavaScript code might be contained in the _files subfolder.