Please don't take this wrong as it is not meant to be an insult of any kind.Just about a year, half time, half on Windows.
I believe some of your Windows OS habits may be pointing you somewhat in a bad direction.
Have you read this.
It's an old article but is spot on.
Deb packages are good I use them when I can.So to conclude this topic: .deb packages are fine for at least these two browsers and sandboxing sandbox affects performance too much to my like.
Another thing that can affect performance is browser ad-ons / extensions.
To many of them can slow things down.
I use Ublock Origin and that's the only browser extension needed imo.
I use Firefox and have the security settings set to maximum levels.
I run in private browser mode always never save any browser history.

