These might be connected. I am not sure about the tooltip one as it actually echoes the browser title. but I think dealing with the missing menu one is the first thing to do.
This is actually caused by a combination of an old – very old – and outstanding WordPress bug and the way your theme might be building the navigation menus, For most users there is no problem as we have all kinds of code in there to try and work around things but with some WP themes these workarounds just fail.
There is, actually, a simple solution and it is the best way to beat the issue. If you go to the menu builder in the WP Admin you can replace the current automatically generated ‘Forum’ menu with a custom menu which just means you have to paste the URL into the little form. This will get you around the issue,
And when that is fixed up we can see if the tooltip has any bearing on this or is something else. I have to say I have never seen such a thing before so it might get interesting!