Firefox Community Forum

I have over 100 open tabs spread over 4 Mac desktops. I can no longer access ANY of them after upgrading to macOS Tahoe 26 and installing ESET Cyber Security Pro. I've used ESET with Firefox for many years without ANY problems. But now I have to choose between uninstalling ESET and being unprotected in order to use Firefox AT ALL. Every single webpage is blacked out with the message below. ESET support says that Firefox needs to issue an update to fix this problem.

Like many, I have Windows 10 and cannot upgrade to Windows 11 without purchasing a new computer. I don't want the upgrade as my desktop computing needs are simple -- checking email and occasional online research. I am looking at 0patch as a solution to Microsoft discontinuing support for Windows 10 and want to know if Firefox will operate compatibly with 0patch providing security patches instead of Microsoft.

I'm not a technical person, so please keep replies simple. At 80 it's tough to keep up with all the changes! Thanks.

My bookmarks, history and passwords have disappeared. I looked at the articles, refreshed firefox, have restarted firefox and my computer multiple times but cannot retrieve them.

This is the message when I start firefox

The bookmarks and history system will not be functional because one of Firefox's files is in use by another application. Some security software can cause this problem.

After instalation Eset Smart Security 18.2.18.0 with full security browsers my Firefox is run only in read-only mode. If I will be disable option Security browser and run Firefox that's working. Next I will be enable option Security browser then Firefox starts with green frame. After close Firefox and next run then starts read-only mode. Eset Team is not fair play becouse resolving problem only disable option Security browser. So why is there an option that prevents Firefox from launching? All my portable browsers without Eset Security working without any kind of problems, for example Tor, Opera.

I use Adguard app for Windows which causes long page loading times in Firefox due to extended TLS Handshakes. I have installed the Adguard certificate in Firefox, have turned off DOH in Firefox, etc. etc. but, the only way that I can get a page to load in a timely manner is by clicking on "reload current page" twice in Firefox. This is a delay in itself and is very inconvenient. I understand that the incompatibility of Firefox with Adguard is a known problem and am wondering whether Mozilla is working on a solution in cooperation with Adguard?

I got the new FF update this morning and noticed shortly after when i got back online a bd_config.cfg file popped up onto my desktop windows 10. I deleted it not thinking anything about it and when back online again and it popped up again in fact everytime i did this it popped up no matter what i did and went online.

It has something to do with BitDefender i figured out uninstalled bit defender re installed it no luck

Refreshed\Reset Firefox with no luck either.

out of nowhere my firefox bookmarks no longer appear. I am getting the following msg

The bookmarks and history system will not be functional because one of Firefox's files is in use by another application. Some security software can cause this problem.

In an attempt to fix this problem, I have done the following:

• closed the browser and re-opened it
• rebooted my computer
• reinstalled my security software
• uninstalled firefox
• Reinstalled firefox

None of these steps have fixed the problem??????

Any ideas would be appreciated!

Moderator note: This question has been edited to correct the formatting.

I wrote yesterday but my post doesn't appear today. Today I got the message about bookmarks and history not functioning and eventually found something in Firefox that said it was probably due to "some security software." I have now gone into Windows settings and my security updates are done, but I have no idea what I'm supposed to do now. This is an extremely annoying and disruptive issue. I see that several other people are experiencing it, so it's interesting that the note next to their posts state that no one else is having the same problem. Can someone please help us all to get our bookmarks and history back?

I am trying to set up a vpn using Proton as a Firefox add-in but Firefox won't let me use it, saying it has invalid credentials. I can't contact Proton because if I enable it as an add-in to Firefox, I can't use my browser. Do you know of any other vpn networks that work securely with Firefox?

The bookmarks and history system will not be functional because one of Firefox's files is in use by another application. Some security software can cause this problem.