Question Black Border on Youtube

[Intequr]

I have a black border which shows up on all the youtube videos I watch

Screensot:

https://imgur.com/a/1ZPNlnI

View: https/imgur.com/gallery/1ZPNlnI

 

[hang-the-9]

This happens only in YouTube videos, everything else goes full screen without that black line? What is the monitor resolution set to and is it the native resolution for the monitor? Using any sort of adapters on it?
If it's only YouTube, try clearing the browser cache. Can also try changing the resolution, maximizing the video and see if that border went away. Then change back to the normal resolution and maximize a video again.

 

[Intequr]

It fixed now I didn't do anything it just went back to normal and the borders stopped popping up