Wow... thanks for this detailed info & guide! I'll probably use the HP laptop with Mint Cinnamon, cause I don't like that old retro look of xfce. A friend told me to try Lubuntu too, so let's see.
I didn't know about that Chrome/ Firefox performance "issue" on old laptops, so thank you! Isn't there a way to disable flatpak at all? Thought on my Manjaro I could disable it, so eventually there is an option there too. OnlyOffice and uBlock were my guesses too. I'll probably set up NextDNS and KDE Connect too.
didn't know they had this feature all the time😳