Firefox Community Forum

Every other day, I open FireFox and may get the following error: XULRunner - This profile was last used with a newer version of this application. Please create a new profile. Also, this error may come up while I already have had FireFox open for a while. Once this error comes up, I check the version, and sometimes the version is older than what it was, meaning, FireFox reverted back to an older version on it's own. I created a new profile, but the error comes back. I removed FireFox and all folders, and the error still comes back. There is nothing I can do to stop the error from showing up again. See attached images. I am on Windows 11 23H2, all windows updates caught up, and the current FireFox browser version is 138.03.

hej, you write oh dear, no print is possible :-((( but you write to me, that I have win10... but it is a new machine with win 11...and firefox does not work, i cant se my mails?!?!!?

When i upgraded Firefox my old profile doesn't show up now. I found my old profile under about:profiles but when i click on the Launch profile in new browser i get this message, "You've launched an older version of Firefox. Using an older version of Firefox can corrupt bookmarks and browsing history already saved to an existing Firefox profile. To protect your information, create a new profile for this installation of Firefox" I did create a new profile but how do i get my old saved data, add ons etc to the new profile?

I have a bunch of profiles set up via "about:profiles". Some of these are associated with different Mozilla accounts, some are not. Today, I wanted to rearrange those profiles to put some older profiles that I do not use as often lower on the page than more recent profiles. I thought I remembered there being an overview text file that included a number for each profile, the folder that profile's information was stored in, etc. When I went looking for that file, I could not find it, so I went looking for help articles and discovered that there is a new profile management tool.

When I tried using the new profile manager via "about:profilemanager", none of my current profiles are visible, so I cannot use that tool to reorder my profiles.

I would be grateful if you could point me to an article explaining how to reorder the profiles in "about:profiles". If that is not possible, I would appreciate a help article explaining the rationale for making these two uses of the word "profile" distinct, the ways in which these profiles are different from each other, and how to transfer settings from the older version to the newer version. I have everything set up just the way I like it within my current profiles and really do not want to have to recreate them from scratch...

I did not ask for and do not want profiles at all. It seems this was added when firefox updated? How do I get back to the old version with no profiles. It also lost all my bookmarks etc. Help would be appreciated.

I have an account with Chewy. When I try to access the link to "My Pet" I receive this message:

400 Bad request Your browser sent an invalid request.

I don't understand why or how to correct it.

My account was probably hacked. I noticed this from an email I received from Mozilla. My account was logged in from Africa, which i noticed from the timezone because the email gives literally no detail. I logged into my account to kick them out but i found out i couldnt because the button didnt work. All the other kick buttons worked except the hackers. Mozilla has done nothing other than to email me.

Good morning, after today's FF update - right click dropdown menus are terrible! Nothing works for me... Opening new windows, new tabs, adding to bookmarks, copying, pasting, etc... How can I turn it off because I can't use it. I need to have a menu like in version 133.0.3. If I can't change it, I will have to change the browser because I can't use it! Thanks for your answer and best regards! Arthur

Suddenly I cannot access one of my email providers [tutanota.com] because, so its error message says, javascript is not enabled my browser [Firefox is my default browser]. BUT javascript is enabled. [I just checked through taking the steps 1) typing "about:config" in Firefox; 2) clicking "accept risk and proceed"; 3) typing "javaScript" in the select preferences name box; 4) looking at the javascript line for "true" or "false".] Javascript was "true". Help. Please advise.

Hello sir/ ma, please help me resolve this issue of unable to reach a particular site called " nimc selfservice modification site" this i have been having access to before.

started receiving this error message while on musify.club. It lets me in, then after a few moments the pop up comes back with same code. after research, it has been deemed that I'm only party affected but I can get in on other devices with no issues from same wifi network. please advise. win 10 pc user. thanks.

I can not get into my Yahoo Email account. When I log in it says, "Something's gone wrong".

I can get into my Email through a different browser on the same computer. This started last 

Wednesday (01-29) or Thursday (01-30). Help.

Thank you for your time. Tony S.

I'm 70 years old and somehow yesterday I pushed a botton that closed out my dashlane password saver and I nned help getting normal settings back please. I can't get into emails etc. Please call me at [edited from community support forum]