Not OP, but I've been using a similar HTML file (local at first, now hosted on GitLab) that does the same thing, though I use it with Firefox and Tree Style Tab to organize hundreds of tabs.
The approach I follow is to be able to set the title of the page as well as the contents, and the tab now acts as a labeled container of other tabs. The contents are stored in the URL, same as OP, so the same caveats apply.