cookie blocker doesn't seem to work properly on Facebook mobile site

Yesterday i upated my Firefox Focus app to the latest version (8.0.25 i think), and the 'block cookies' may not be working properly, as now everytime i open a link or a new tab and return to facebook, i find my account logged out. In the past, this was not a problem and i remained logged in even if i left the site for a moment. My current block cookies option is for 3rd-party trackers only, and trying any of the options does not solve the problem.