FF so slow compred to Brave

[dr.watson]

Anyone with ideas why FF is so laggy and slow. I have done all the speed up things advised but still it is as slow as 10 years ago.
I tried Brave and wow it is blisteringly fast in loading pages and rendering so use that more than any other browser. I can have 50 tabs open with no loss of speed.
So what is the problem?
Am I missing something?

Using on Win10.

NB. Have been a FF user from the beginning and currently using quantum.

[Brummelchen]

reset your profile or uninstall your current antivirus (if not windows defender)

[DanRaisch]

I have done all the speed up things advised

Since you didn't say where you found the "speed up" advise we don't know what you have tried. Rather than"resetting" the profile, have you tried starting Firefox in Mozilla Safe Mode? http://kb.mozillazine.org/Safe_mode
If no improvement using Safe Mode, do you have the same problem if you create a new profile and test it with no extensions or non-default themes installed?
http://kb.mozillazine.org/Profile_Manager
and
http://kb.mozillazine.org/Creating_a_ne ... on_Windows

[therube]

I have done all the speed up things advised

Who advised & what were they?

FF is so laggy and slow.

Likewise, in what way & where is it?