@acerswap This seems to be a bug with
browser.js, which is a script that runs in the browser to patch things out of various websites (think annoying thing's like "Why use Opera, when you can use X", "Your browser isn't supported, use X instead").
In the latest version it seems to be bugged and puts the version number on every page (including nested ones! yuck) instead of only on it's own information page at
For now, until it gets fixed, you'll need to open a page to
opera://browserjs and then click "disable browser.js ... for this session". Unfortunately it'll come back whenever you reopen the browser until it gets fixed.