As the title says, while running opera in fullscreen on his own virtual desktop, showing the top bar generate a white strip on the bottom as it hides again, like shown in the picture: https://imgur.com/a/zasHywW
And every time i toggle the top bar the white strip gets bigger and bigger. in the picture above i did it multiple times to exaggerate the effect.
Refreshing doesn't help. Although i noticed that switching between tabs reset the page to his normal layout.
The example picture is only an example as this behaviour occurs in almost every site i bothered to check.
No extension except from built in ad blocker, and flow.