Application error: a client-side exception has occurred (see the browser console for more information).

Fix for RangeError: invalid language tag and client-side exceptions in Firefox on Linux Hi everyone, I was experiencing persistent JavaScript errors in Firefox on Linux … (kàsi)

Fix for RangeError: invalid language tag and client-side exceptions in Firefox on Linux

Hi everyone, I was experiencing persistent JavaScript errors in Firefox on Linux when loading certain modern websites (e.g., built with React or Next.js). The browser console showed messages like:

   RangeError: invalid language tag: "chrome://global/locale/intl.properties"
   A client-side exception has occurred (see the browser console for more information)
   React error #418 with minified stack traces

This happened even in Safe Mode, with all extensions disabled, cookies/cache cleared, and Enhanced Tracking Protection off. ✅ Root cause and fix:

Turns out the issue was related to missing or broken locale configuration in Firefox. To fix it:

   Open about:config
   Create a new string entry:
       Name: intl.locale.requested
       Value: en-US (or fr, en-GB, etc. — any valid locale)
   Restart Firefox

After adding this key, all affected pages started working correctly. The invalid "chrome://global/locale/intl.properties" error in intl.accept_languages disappeared as well — it seems that was just a side effect of the missing locale setting. 🔁 Summary:

If you’re seeing RangeError: invalid language tag and React crashes, try adding intl.locale.requested manually. This fixed the issue entirely for me on Linux.

Hope this helps others!

Asked by Clément 16 àwọn wákàtí sẹ́hìn

History wiped on exit with options not working as per requirements.

Ok so I usually choose these option to remember history and from time to time delete Browsing & download history and Temporary cached files and pages. https://asset… (kàsi)

Ok so I usually choose these option to remember history and from time to time delete Browsing & download history and Temporary cached files and pages.

https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2025-06-28-08-45-55-a5277f.png

Note: I have "Open previous window and tabs" ticked in general settings which also has a restore previous session option in the history menu. This brings back previous session with tabs etc as is when I close FF. https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2025-06-28-08-45-51-cf2daf.png

I thought I could automate this on exit but don't think its working right. So I change the option to "use custom settings for history" and tick all three options:

Remember browsing and download history Remember search and form history Clear history when Firefox closes For "Clear history when Firefox closes" I ticked Browsing & download history and Temporary cached files and pages. https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2025-06-28-08-45-43-b10213.png

The issue is the restore session option is missing and FF opens with all previous tabs gone. I am frankly not even sure what else is missing such as cookies, site data etc. Is this meant to work like so?

Asked by Mrsash 2 àwọn ọ̀sẹ̀ tó kọjá

Last reply by Mrsash 21 àwọn wákàtí sẹ́hìn

about:support page many configs are blank when i change my profile

I use scoop to install firefox. then i changed the default profile to the Scoop profile. Then i tried to log in the mozilla account but it keep saying that it cannot cont… (kàsi)

I use scoop to install firefox. then i changed the default profile to the Scoop profile. Then i tried to log in the mozilla account but it keep saying that it cannot continue because cookies or localstore are disabled. Then i checked the about:support page like i said in the titile, many configs are blank. Maybe some problems with the profile i guess. I also opened a issue in Scoop githup repo, they cant reproduce my problem. Where could go wrong? Any help would be appreciate!

And this is the issue i post on github https://github.com/ScoopInstaller/Extras/issues/15770

Asked by LOYINuts 22 àwọn wákàtí sẹ́hìn

The error in downloading files is causing abnormal web browsing.

There was an error when downloading files with the browser, indicating that there was a problem with the file directory. The download failed, and changing the file direct… (kàsi)

There was an error when downloading files with the browser, indicating that there was a problem with the file directory. The download failed, and changing the file directory was still ineffective. Then, it resulted in a situation where no web pages could be opened, as if the network was disconnected. After closing the browser and reopening it, it returned to normal, but the download still could not be used. This problem has existed since versions 115.24 and 115.25.

Asked by hyrjdq 23 àwọn wákàtí sẹ́hìn

pop setting

The pop settings in the browser show it is blocked but I can't find an option to unblock it

Asked by gippy3568 1 ọjọ́ tó kọjá

Firefox does not play sound despite being attributed to correct device. All other apps OK.

What the title says. Firefox just isn't playing any sound whatsoever. Troubleshooting: Volume mixer indicates that Firefox is using my speakers, along with all other… (kàsi)

What the title says. Firefox just isn't playing any sound whatsoever.

Troubleshooting:

  • Volume mixer indicates that Firefox is using my speakers, along with all other apps. When playing a YouTube video, the green bar is not bouncing. However, all other programs that play sound do so successfully and their green bars are bouncing (see attachment).
  • Other web browsers play sound successfully.
  • Restarting Firefox and my computer did not help.
  • Switching the default sound device and changing back did not help.
  • Changing to headphones made no change.
  • Tabs are not muted.
  • Autoplay settings in about:preferences showed that audio and video were disabled, however changing this setting to allow video and audio, then restarting both Firefox and the computer did not fix the problem. I have no idea how that setting was even changed to begin with. O_o
  • Started Firefox in troubleshooting mode; still no sound.
  • Started Firefox in a different profile; still no sound.
  • Started Firefox in private mode; still no sound.
  • Tried ending the audiodg.exe process in task manager and restarted; still no sound.
  • Double checked media.autoplay.blocking_policy, was set to 0.
  • Double checked media.block-autoplay-until-in-foreground -- changed from true to false, restarted Firefox; still no sound.
  • Disabled hardware acceleration; still no sound.
  • Refreshed Firefox; still no sound.
  • Complete uninstall, including the usage of BCUninstaller to uninstall "leftovers". Reinstalled. Still no sound.

I have Apollo installed on my computer and I've reached out to them before for similar issues, but the dev was insistent that Apollo does not cause sound issues. I'm somewhat sceptical, but they're not being helpful at all so I thought I'd ask here, and disclose usage of Apollo so that all bases are covered.

Thank you for your time.

Asked by Umbravita 2 àwọn ọjọ́ tó kọjá

Last reply by Umbravita 1 ọjọ́ tó kọjá

LastPass icon not working

When I click on the grey Last Pass icon, a "set preferences" screen is shown. The strictly necessary box is selected and I cannot change it. The Voluntary data collecti… (kàsi)

When I click on the grey Last Pass icon, a "set preferences" screen is shown. The strictly necessary box is selected and I cannot change it. The Voluntary data collection box is clickable but does not make any difference if it is checked or unchecked. The screen is locked, no matter what I click or unclick. The only thing that I can do is to click the grey LP icon which closes the window.

On two other very similar computers, when the grey icon is clicked, I can search for passwords, alerts, account, etc. Why does the icon work on this computer. I've deleted the addin, deleted Firefox and reloaded several times.

Thank you

Asked by cruisertwo 1 ọjọ́ tó kọjá

Google search engine.

Hi, Google, is my search engine of choice on Mozilla Firefox, and the Os on my computer is Windows 10. Google search is no longer active from any scroll down or top tab b… (kàsi)

Hi, Google, is my search engine of choice on Mozilla Firefox, and the Os on my computer is Windows 10. Google search is no longer active from any scroll down or top tab bar. Have a nice day.

Asked by zx10rcurvsrr 1 ọjọ́ tó kọjá

login password for bank

I currently use an extension to fill passwords, so I have passwords in firefox turned off. However, one of my logins shows an 'eye' which I believe is firefox wanting to… (kàsi)

I currently use an extension to fill passwords, so I have passwords in firefox turned off. However, one of my logins shows an 'eye' which I believe is firefox wanting to provide the password. I don't know how the eye got there, as all my other logins work with the extension. I have to go to the extension and physically copy the password to paste it in the password box. If I go to firefox settings, I have no passwords set. How do I get rid of the 'eye' for that login?

Rick

Asked by rrsum 1 ọjọ́ tó kọjá

Pinned tabs and tab groups disappeared

I run FF on a Windows desktop. I have 5 pinned tabs and one tab group. Today when I opened FF all of these had disappeared. This has happened before, so I have a screensh… (kàsi)

I run FF on a Windows desktop. I have 5 pinned tabs and one tab group. Today when I opened FF all of these had disappeared. This has happened before, so I have a screenshot of the 5 tabs and can restore those, but I didn't make one of the tab group (given that the whole point of it was to SAVE the tabs), and unfortunately those were the result of a lot of time spent researching.

Is there something I can to do make sure these tabs all actually get saved from one session to the next? This unreliability of FF wastes a lot of time and starts me thinking about going back to Chrome which at least has the virtue of more stability. What is the point of all these features (I was really happy when you created the tab groups) if I can't rely on them?

Asked by sleagolden 1 ọjọ́ tó kọjá

startup crash

Is there any update on this issue. Do I just need to download a different browser and stop using Firefox?

Thank you.

Asked by Mike 2 àwọn ọjọ́ tó kọjá

Last reply by Mike 1 ọjọ́ tó kọjá