[Bug]: New installation of Floorp cannot log in to Firefox account for synchronization

[Gokou-Ruri]

Pre-Submission Checklist

• I have checked the existing/closed issues to ensure this issue has not already been reported.
• I am using the latest supported version of the browser.
• I have tried disabling all browser extensions/add-ons to rule out interference from these.
• I have tried clearing the browser cache and cookies.
• I have checked with a new profile and the issue still occurs.
• I have provided detailed step-by-step instructions on how to reproduce the issue.
• I have included relevant screenshots or console outputs.
• I have checked that this problem is not occurring in the latest version of Firefox ESR.
• This issue is specific to this browser and does not occur in other browsers.

Bug Summary

I installed Floorp on both macOS and Windows platforms, but neither can log in to the Firefox account. After entering the authorization code from the email, it always prompts Something went wrong. Please close this tab and try again.

Reproduction Steps

1.Install the browser
2.Select login account from the menu
3. Enter account/password/authorization code
4. Jump to the error page

Expected Behavior

Successfully logged in to the account and synchronized account data.

Actual Behavior

.

Screenshots

Browser Version

Version 11.24.0 (64-bit) | Firefox: 128.9.0

Operating System

macOS 15 & Windows 11

Additional Context

No response

[NaniNoni]

I just did this about ah hour ago on Winodws 11 and it worked totally fine on the latest release. Maybe the problem is somewhere else? Like with your Mozilla account? The only difference I can identify between our setups is that I used a 2-FA app instead of email.

[Gokou-Ruri]

I just did this about ah hour ago on Winodws 11 and it worked totally fine on the latest release. Maybe the problem is somewhere else? Like with your Mozilla account? The only difference I can identify between our setups is that I used a 2-FA app instead of email.

Yeah, I use 2FA too, but when I try to log into my Firefox account on floorp, it asks for a verification code. It works fine on Firefox for Windows and Android—I can log in and sync no problem—but it just won’t work on floorp. Kinda weird, right?

[Olexijl]

I have no problems here at all. I don't use 2FA though. Go to your Mozilla account (in Firefox), connected devices, and check what is listed here. Disable connection to everything unneeded, so only 1 connected device (Firefox) remains. Try loggin in with Floorp again.

PS: according to their new Terms of Use, they can disable access to Mozilla account for everyone not using Firefox. Like using Floorp. But since it is working for me just fine, they did not disable access yet.

[Gokou-Ruri]

No issues here at all. I don't use 2FA though. Go to your Mozilla account (in Firefox), connected devices, and check what is listed here. Disable connection to everything unneeded, so only 1 connected device (Firefox) remains. Try logging in with Floorp again.
[Bug]: New installation of Floorp cannot log in to Firefox account for synchronization · Issue #1637 · Floorp-Projects/Floorp
PS: According to their new Terms of Use, they can disable access to Mozilla account for everyone not using Firefox. Like using Floorp. But since it is working for me just fine, they did not disable access yet.

Thank you, you are right, Firefox limits the number of devices that can be logged in, and you cannot log in to a new device if the number is exceeded.