I went through this forum trying to find others who face the same issue, but didn't. It's a little bit surprising, because it happens to me in 4 different computers — though not on mobile, which makes me think it's a theme issue.
Every time I click on a link (e.g. "go to first unread", or I try to navigate to another page), I get the "Leave Site? Changes you made may not be saved" browser alert pop up. Of course, there are no changes to be made; I'm not composing any message, only browsing. This is clearly some bug in one of the forum's .
js files.
This happens both on Chrome and Firefox — also in incognito/Guest windows; it's not a cookie/cache issue.
It only happens when I'm logged in, by the way.
Any knowledge about this?