I have a 2017 2 TB port non Touch Bar 13 inch MacBook Pro running 10.15.7 (Catalina) that doesn't bother me.
I can use Safari 13 on it. I can use Firefox LTS (currently 78) on the same laptop, no issues.
I cannot use the current Firefox with the "Proton" UI (currently 92).
I also noticed that Safari 14 on both Mac OS 10.15 and 11 bother me in a similar way to the current Firefox.
I can use Safari 14 on iOS 14.8 on my iPhone 6s.