Safari Youtube buttons are non-clickable while in fullscreen.

if your cursor is unable to click (it has no effect) when watching a video full screen do this steps

1. pull down the “Safari” menu and choose “Preferences”
2. Select the “Search” tab.
3. Uncheck the box next to “Show Favorites” under the 'Smart Search Field' section.
4. Close Preferences as usual.

Ive got the same issue! and I have YouTube on whitelist with adblocker as YouTube got really annoying months ago for those with adblocker on Safari so I whitelisted it, now I dont usually watch stuff in full screen mode on YT hence didn't notice this issue until now but today I was watching a vid and I couldn't do anything, even tried turning the Adblock on and still nothing, anyone had any luck with sorting this issue?

There is something specific to your system that is causing this.

Please run Etrecheck and post its report here.

No obvious red flags in the report.

Did you test in a different user account to see if the same problem occurs?

Wow this actually worked for me, this bug has been occurring since I installed Catalina and I was running out of options. Thanks!

it fixed the issue, finally !!! safari is awful, only use it to save battery.