So..
I found a “fix” to my problem. More like a workaround..
With my login if I try to create/edit a tab it goes as I previously said into an infinite loading until it crashes (see the image in the post above).
Out of curiosity I created a brand new user with admin rights and to my surprise the problem isn’t there anymore.. I can edit/create and it works perfectly fine!
The only thing that comes to my mind is related to this thread (https://www.ads-software.com/support/topic/not-loading-16/) about how I had hidden some of the options on “Options on the screen”.
