Firefox 70.0 does not load some website pages completely. Ubuntu 18.04

I am using Ubuntu/Firefox for several years.
Now some pages do not load completery, progress icon moves permanently.
Examples: "pCloud.com" "facebook.com" "Webmin/File Manager" and others Other pages of those websites load normally.
I tried restart with plugins disables but nothing changed.
Same webpages load okay with Chrome.

about:config
dom.storage.next_gen
Set the preference to False

results in

According to this creating a new profile would solve the entire issue. I don't want to create a new profile.
At least those pages are loading normally now.