Youtube.com - reporting flash needs updating. Opera 10.53

Youtube.com - reporting flash needs updating. Opera 10.53

About 5 days ago, I was happily watching youtube videos in Opera 10.53. Between one video and the next, youtube suddenly stopped working. I didn't close tabs, or opera, or browse away from youtube at any point.
One minute it worked, the next, I get this:

That's weird, I think.
Oh well, click the download, new flash player, restart opera...

Same problem.
Odd... maybe something went wrong with the install... nope.

Check another browser... youtube is ok.

Ok, try downloading and installing flash with a different browser, but get the opera version, maybe something went wrong... nope.
Ok, maybe opera broke. Let's reinstall opera 10.53... nope.

Ok, time to hunt for solutions. Found a bunch of people complaining about a similar problem last month (which I never experienced).
Found there was a UserJS workaround - tried it... no dice. Youtube no longer tells me that I need a new version, but it still doesn't play video, either.
Found opera released a fix! just search for updates, it'll get the latest browser.js, and problem goes away!... No it doesn't.
Clear cookies!... nope
Clear cache!... nope
Clear both!... nope
Do all combinations of the above, with and without UserJS fix!... nope.
Change assorted opera configs, like delayed plugin startup, etc (forget which exactly, I've tried a bunch)... Still nothing.
Edit site preferences to allow java, don't allow java, use cookies, don't use cookies. Report as all other browsers... still nothing.
Clearing cache after all of those... nothing.
Wait! Someone says it works if you watch via someone's user page...no it doesn't.
How about embeds? Nope

Downloaded latest beta build of opera, hoping maybe something's changed - got 10.54:3390 - well, now my speed dial is bold and ugly again, but youtube still doesn't work.

Searching for people posting about this problem in the last week or so - can't really find anything.
Seems people had my problem a month ago, and then it got fixed, and now I'm the only person with the problem.

I'll stress that I was watching a video. Clicked on a related videos link to watch another one, and suddenly my flash isn't up to date.
No recent software installs.
Only recent update was opera 10.52 to 10.53.

I'm completely out of ideas here. Can anyone help me debug this?

Solved:
settings -> quick preferences -> enble plug-ins.

I have no idea why this all came out (how could i see videos up to now if my plugins were disabled?)

See if it works for any of you...

Thanks for any feedback.

*RN