Firefox font size
I've looked everywhere to find the reason why in Firefox Quantum suddenly the Gmail interface was displaying a tiny font. Only the Gmail interface had this problem, that I know off. Other sites were working properly.
Update 22 August: almost all sites have the problem: Google, webmail clients etc. [Topic subject adjusted]
After a online search I found nothing usefull. It's not a zoom issue, I repeat not a zoom issue.
I started checking my addons one by one. Simply disabeling the F-Secure KEY addon for Firefox restored the font to normal. Turning the addon back on made the Gmail interface font unreadable again.
Is this a known issue and if yes what is the eta for a update/fix?