Yesterday, I uploaded the following video and posted it to this thread: viewtopic.php?f=124&t=73456
YouTube was really slow yesterday, and the video took ages to clear its checks, but I think that's irrelevant to the question.
The thing is, when I try to watch the embedded video, after a few seconds of trying I get this:

but if I click the link to watch it on YouTube directly, I can see it just fine.
I originally thought it was something wrong with the video settings (or the checks problem) but, no, I can watch the video on another browser where I'm not signed in to Google, I can see it on my phone and I can also sign out from Google on this browser and the video works just fine too. However, as soon as I sign back in to Google, I can't watch the video as an embedded video on the forum; I have to watch it on YouTube.
I can watch other videos not made by me on this forum, it's only my one (I haven't checked my other videos yet). So, does YouTube/Google have some weird thing where creators cannot watch their own videos if they have been embedded on another site?
[edit]I tried another one of my videos - same problem.[/edit]