UI bugging when I middle clicked a link

[Nissyaniss]

Describe the bug
When opening a page with middle click the entire UI bug and it's nearly impossible to read.
Seems to be only on firefox because when using chrome I do not have any problems.
But I may be dumb.

To Reproduce
Open any tab of 42intra in firefox with middle click

Expected behavior
The UI to work correctly and be readable when opening with middle click

Screenshots
Jut click :

With middle click :

Desktop information (please complete the following information):

• Browser Firefox
• OS Ubuntu 20.04 LTS

(PS : I'm not very smart so maybe so it's caused by something I've got (for example i have the Dark Reader extension but it's deactivate on the intra so i don't know))
(PS1 : I'm french don't judge my writing)

[FreekBes]

I've also experienced this issue on the same OS and browser, seems to be something with Improved Intra indeed. A quick reload fixes this issue, but a long-term solution would be nice at some point. I will look into this