Q: Why is YouTube not working with Safari all the sudden?

Hi ..

YouTube content requires Flash.

Open System Preferences > Flash Player then select the Advanced tab.

Click Delete All under Browsing Data and Settings

Not empty the Safari cache.

From your Safari menu bar click Safari > Preferences then select the Advanced tab.

Select:  Show Develop menu in menu bar

Now click Develop from the menu bar. From the drop down menu click Empty Caches.

Now try a video. If you still have problems, try troubleshooting Safari extensions.

From the Safari menu bar click Safari > Preferences then select the Extensions tab. Turn that OFF, quit and relaunch Safari to test.

If that helped, turn one extension on then quit and relaunch Safari to test until you find the incompatible extension then click uninstall.

Appears to be a glitch at the Google end of things:

https://productforums.google.com/forum/#!topic/youtube/nQ-eI0VeVXQ%5B1-25-true%5 D

"YTLauren" in the thread is the YouTube employee.

This helped and resolved same issue YOUTUBE not displaying video image. Turned out to be ADBLOCK PLUS preventing videos to run.

Deleting extension worked out!
Thank you!

Had the same problem, but for me it was the Youtube Center Extension that was causing problems.. Deactivated it and refreshed the site and all good..:)

I just wanted to say that deleting the Adobe data and clearing the Safari cache does not do a thing.

I have no You-Tube extension installed or enabled either.

The problem I have is that I can do to a page, a video, and watch it fine.  But if I am logged in and

try to make a comment the window says opening, and just sits there and never gives me a cursor.

It works fine if I open up Chrome or another browser, but You-Tube seems to really hate Safari.

Thank you as this solved the issue on my MacBook Air

Thank you very much. It worked wonders..