I want to keep Firefox bookmarks list as a separate file, on another partition, if it is possible.
Or is there a way to create some kind of backup of the bookmarks list ?
I want to prevent losing all my bookmarks after an infection and reinstalling OS.
Did you try to export the bookmarks?
Open show all bookmarks (ctrl + shift + B) and then import and back up. Back up!
Also it is saved at places.sqlite. The path will be similar to C:\Users\NAME\Application Data\mozilla\Firefox\Profiles\ select the profile \
The best way is to keep your profile in another location/Drive
Open CMD in the folder where firefox installed
select new profile. Set the location of Firefox profile location name it
Now you can have your all settings addons in another local disk
open firefox -p select Create new profile name it the old name
Select location to the location where your profile is saved.
To answer the backup part of your question, give Xmarks a try. It keeps an online repository of your bookmarks, and there are plugins/add-ons/extensions for every major browser. Free to use.
So you can access them manually online via my.xmarks.com, sync them to your phone and tablet, to your home desktop, to your workstation, and any other device.
Another option is to enable the built-in sync features of Firefox or Chrome.