Firefox Community Forum

I installed Firefox years ago. This morning, when I click on the browser icon, I get this message: Error platform '127.0.2' is not compatible with minVersion>= 127.0.1 maxVersion<= 127.0.1

What is going on? The browser updates itself so I don't do anything. But now, it doesn't work. I use an alternate browser to send this message to you.

Roughly every 2 weeks I backup important files to a external hard drive.

One of the things I always backup is my Firefox profile. I have been doing this for years without any problems.

I 7zip my profile and copy it to the hard drive.

I tried to do this yesterday (July 25 2025), and was getting access denied messages for files in the profile. So I tried to simply copy the profile. Same thing access denied.

I cleared the history, used wise disk cleaner, rebooted my machine and tried again. Same thing access denied when trying to backup or copy the profile.

I am assuming that this is happening since 141 because I updated Firefox since the last time I backed up my profile, and never had a problem previously.

Could anyone have an idea what the problem is? Thank you for your time.

Sync just does NOT work. I installed FF on my Mac brand new and fresh... brand new machine. Signed into Sync. NOTHING. After 6-7 HOURS... nothing. It just gets NOTHING AT ALL from my Windows Desktop.

I've signed out of ALL Firefox/Mozilla sync sessions... signed in clean- all browsers are up to date. And the about:sync-log page shows a LONG streak of errors... NON STOP ERRORS.

Why?! Why can't we just sync extensions to install and bookmarks across machines? How is this that hard for Mozilla?!

The sync-log page list: File:error-sync-1714085057059.txt 6 KB 4/25/2024 17:44:17 File:error-sync-1714088658041.txt 18 KB 4/25/2024 18:44:18 File:error-sync-1714189161327.txt 6 KB 4/26/2024 22:39:21 File:error-sync-1714498425099.txt 13 KB 4/30/2024 12:33:45 File:error-sync-1714588968223.txt 10 KB 5/1/2024 13:42:48 File:error-sync-1714589121080.txt 9 KB 5/1/2024 13:45:21 File:error-sync-1714600674960.txt 7 KB 5/1/2024 16:57:55 File:error-sync-1714604277834.txt 24 KB 5/1/2024 17:57:57 File:error-sync-1714838021899.txt 24 KB 5/4/2024 10:53:41 File:error-sync-1714839602488.txt 11 KB 5/4/2024 11:20:02 File:error-sync-1714839613709.txt 10 KB 5/4/2024 11:20:13 File:error-sync-1714844303035.txt 16 KB 5/4/2024 12:38:23 File:error-sync-1714844919123.txt 15 KB 5/4/2024 12:48:39 File:error-sync-1714846872373.txt 17 KB 5/4/2024 13:21:12 File:error-sync-1714846956569.txt 12 KB 5/4/2024 13:22:36 File:error-sync-1714941772713.txt 15 KB 5/5/2024 15:42:52 File:error-sync-1714941774043.txt 14 KB 5/5/2024 15:42:54 File:error-sync-1714941849730.txt 14 KB 5/5/2024 15:44:09 File:error-sync-1714942633097.txt 14 KB 5/5/2024 15:57:13 File:error-sync-1714942674714.txt 48 KB 5/5/2024 15:57:54

Day after day and attempt after attempt of failures for a basic function of the browser.

Here is the text of the latest log and showing constant connection errors- mind you NOTHING is breaking on my internet as I'm often streaming things and watching stuff while surfing, or others in the house are. Our connection, and Firefox getting online, are all working fine. I am at a loss. I don't understand how this is so terribly broken out of the box that you can't just sign in and let it talk to their servers. I know Google has billions behind Chrome, but this shouldn't be so 1990's bad by comparison to Chrome sync.

1714081299909 Sync.SyncScheduler DEBUG Next sync in 3600000 ms. (why=schedule) 1714081300746 Sync.SyncScheduler DEBUG Network link status changed to "changed". Offline?: false 1714082945349 Sync.SyncScheduler DEBUG Network link status changed to "changed". Offline?: false 1714082945373 Sync.SyncScheduler DEBUG Network link status changed to "down". Offline?: false 1714082945373 Sync.SyncScheduler DEBUG Clearing sync triggers and the global score. 1714082945374 Sync.SyncScheduler DEBUG Next sync in 3600000 ms. (why=schedule) 1714085055761 Sync.SyncScheduler DEBUG Woke from sleep. 1714085056643 Sync.SyncScheduler DEBUG Network link status changed to "changed". Offline?: false 1714085056786 Sync.SyncScheduler DEBUG Network link status changed to "up". Offline?: false 1714085056786 Sync.SyncScheduler DEBUG Network link looks up. Syncing. 1714085056899 Sync.SyncScheduler DEBUG Network link status changed to "changed". Offline?: false 1714085056902 Sync.Service DEBUG User-Agent: Firefox/125.0.2 (Windows NT 10.0; Win64; x64) FxSync/1.127.0.20240419144423.desktop 1714085056902 Sync.Service INFO Starting sync at 2024-04-25 17:44:16 in browser session V0xN5aUmAS9A 1714085056902 Sync.SyncScheduler DEBUG Clearing sync triggers and the global score. 1714085056904 Sync.Status INFO Resetting Status. 1714085056904 Sync.Status DEBUG Status.service: success.status_ok => success.status_ok 1714085056904 FirefoxAccounts DEBUG FxAccountsProfileClient: Requested profile 1714085056904 FirefoxAccounts DEBUG getOAuthToken enter 1714085056905 FirefoxAccounts TRACE getCachedToken returning cached token 1714085056905 FirefoxAccounts DEBUG getOAuthToken returning a cached token 1714085056905 Services.Common.RESTRequest DEBUG GET request to https://profile.accounts.firefox.com/v1/profile 1714085056905 Sync.SyncAuthManager INFO Getting sync key 1714085056905 FirefoxAccounts DEBUG getOAuthToken enter 1714085056905 FirefoxAccounts TRACE getCachedToken returning cached token 1714085056905 FirefoxAccounts DEBUG getOAuthToken returning a cached token 1714085056905 Sync.SyncAuthManager INFO Getting a sync token from: https://token.services.mozilla.com/1.0/sync/1.5 1714085056905 Sync.SyncAuthManager DEBUG Getting a token using OAuth 1714085056905 Services.Common.TokenServerClient DEBUG Beginning OAuth token exchange: https://token.services.mozilla.com/1.0/sync/1.5 1714085056906 Services.Common.RESTRequest DEBUG GET request to https://token.services.mozilla.com/1.0/sync/1.5 1714085057025 Services.Common.RESTRequest DEBUG GET https://profile.accounts.firefox.com/v1/profile failed: 2152398878 - NS_ERROR_UNKNOWN_HOST 1714085057025 FirefoxAccounts ERROR Background refresh of profile failed: {"name":"FxAccountsProfileClientError","code":null,"errno":998,"error":"NETWORK_ERROR","message":"[Exception... \"NS_ERROR_UNKNOWN_HOST\" nsresult: \"0x804b001e (NS_ERROR_UNKNOWN_HOST)\" location: \"JS frame :: resource://services-common/rest.sys.mjs :: onStopRequest :: line 478\" data: no]"} 1714085057031 Services.Common.RESTRequest DEBUG GET https://token.services.mozilla.com/1.0/sync/1.5 failed: 2152398878 - NS_ERROR_UNKNOWN_HOST 1714085057031 Sync.SyncAuthManager ERROR Non-authentication error in _fetchTokenForUser: TokenServerClientNetworkError({"error":{}})(resource://services-common/tokenserverclient.sys.mjs:28:36) JS Stack trace: TokenServerClientNetworkError@tokenserverclient.sys.mjs:51:16 _tokenServerExchangeRequest@tokenserverclient.sys.mjs:235:13 1714085057031 Sync.Status DEBUG Status.login: success.login => error.login.reason.network 1714085057031 Sync.Status DEBUG Status.service: success.status_ok => error.login.failed 1714085057031 Sync.SyncAuthManager ERROR Failed to fetch a token for authentication: TokenServerClientNetworkError({"error":{}})(resource://services-common/tokenserverclient.sys.mjs:28:36) JS Stack trace: TokenServerClientNetworkError@tokenserverclient.sys.mjs:51:16 _tokenServerExchangeRequest@tokenserverclient.sys.mjs:235:13 1714085057032 FirefoxAccounts TRACE not checking freshness of profile as it remains recent 1714085057055 Sync.Resource WARN GET request to https://sync-1-us-west1-g.sync.services.mozilla.com/1.5/209631697/info/collections failed: [Exception... "The lookup of the hostname failed" nsresult: "0x804b001e (NS_ERROR_UNKNOWN_HOST)" location: "<unknown>" data: no] No traceback available 1714085057056 Sync.Status DEBUG Status.sync: success.sync => error.login.reason.network 1714085057056 Sync.Status DEBUG Status.service: error.login.failed => error.sync.failed 1714085057056 Sync.ErrorHandler ERROR Sync encountered an error: [Exception... "The lookup of the hostname failed" nsresult: "0x804b001e (NS_ERROR_UNKNOWN_HOST)" location: "<unknown>" data: no] No traceback available 1714085057056 Sync.SyncScheduler DEBUG Next sync in 3600000 ms. (why=reschedule) 1714085057057 Sync.Telemetry INFO Early submission of sync telemetry due to changed IDs/NodeType 1714085057059 Sync.Service DEBUG Exception calling anonymous function: [Exception... "The lookup of the hostname failed" nsresult: "0x804b001e (NS_ERROR_UNKNOWN_HOST)" location: "<unknown>" data: no] No traceback available

I was on the ESR channel and after the recent updates to 142.01 or 141 the ESR is missing from the about Firefox. I had got the tab groups option a few updates back and liked it. This latest update changed how a tab group collapses, instead of showing only the tab group name and collapsing all the tabs it leaves one open wasting space when I have several other tabs open. At least I don't see any sign of the annoying AI junk getting in the way yet. I thought you had a choice to stay on the ESR channel according to this link and others. https://support.mozilla.org/en-US/kb/firefox-support-windows-10-end-support I'll probably be forced to update to Windows 11 to do my taxes next year but I thought at least I could stay on the ESR channel to avoid new features getting in the way.

I've added https://x.com as an exception site but it is still blocked.

This is outright censorship which is something [edited] do.

Tell me how to fix your browser so I may access x.com again or I stop using Firefox forever.

basically just the title. In the last couple days youtube.com specifically has been borderline unusable for me on firefox. All other websites work fine for me on firesfox and youtube has no issues on other browsers.

Updated to esr 128.14 Now Reddit (Redgifs) Hosting site for gifs crashes Firefox and cripples my PC. I've tried restarting in safe mode, then refreshing Firefox. Nothing is working. Reddit support just has an issue with the Gifs not playing, but nothing as extreme as what iam experiencing. I believe it may be something is preferences or a codec or something that was changed in the recent update. Any advice/ help would be great. Edit: OS is windows 10 latest updates Amd- Ryzen 7/32gig 3.20 ghz PC. So can handle a little bit of heavy browsing.. FF 128.14 esr Ext- Ublock Origin

       Search By Image 
       Flash and Download Video. 

Even with Addons disabled still occurs. Really at a loss here.

Hello, I have problem with firefox. When I try download from facebook page files .docx, .xlsx (Microsoft Office) Firefox automatically download it as PDF and file is broken. I don't know how to repair this. Please help, it is very frustrating.

I've posted before but no answer as to why Firefox labels Paypal as an unsafe site. I don't know where to change settings to allow it without the warning. I've just ignored the warning and continued but it is annoying.

Since latest upgrade (1/16/2026) I cannot log in to Outlook email. This is specific to Firefox 147.0.1 (Chrome and Pop Peeper logins to Outlook work fine). I tried clearing cache, updating, restarting, rebooting, trouble-shooting mode, private window etc. to no avail. I get 400 error from Outlook.

Greetings Ya'll, Firefox Bookmarks are no longer being initially placed in "Other Bookmarks, they are now being placed in the "Bookmarks" that is under the "Open Application Menu" Tab.

I've found that the "New Bookmarks" can be "Dragged" as a copy to "Bookmarks", from the "Bookmarks" located in the menu, for they will stay there unless I delete them

I can not move the "Bookmarks" back to "Other Bookmarks"

Would I lose My Bookmarks, If I "Refresh" Firefox, as suggested in the "Troubleshooting Section? If there is a chance of this happening then that would Absolutely Be Catastrophic!!

Dear Support Team,

After updating to last Mozilla Firefox version (126.0.1) all my ngx-datatable tables are overlapping all rows over the first one even if the entire height of the table is correct calculated.

This is a blocking point. I need assistance urgently.

How come FF translates sites in tiny, irrelevant languages like Bulgarian, but not from major languages like Chinese and Arabic?!?

I wish I could dump Edge, but this FF deficit forces me to keep Edge on my computer...

I'm having issues using Firefox with the Facebook site. Groups are slow to load and sometimes the chat and notification windows take forever to load with shimmering panels or a wait cursor displayed. I've cleared the cache and deleted the cookie, but that didn't rectify the issue. I don't have a problem with Edge.

Majority of the songs do not play and I'm given with a pop-up, "Spotify can't play this right now. If you have the file on your computer you can import it."

I will play a song from a playlist and is given that pop-up, it will continue skipping to the next song until it plays, but only for 9-10 seconds until the song mutes, to specify, the dot (when hovered on the progress bar) will still move, indicating that "it's playing".

Some clarifications: 1. I use Spotify Desktop app (windows), Spotify App (android), and Spotify Webplayer on Chrome and Firefox. Everything works just as fine on all of these, except for Spotify Webplayer on Firefox. 2. Skipping to a later timestamp does not unmute the song. 2. I have Spotify Premium 3. I have no VPN 4. I am running Firefox with an ad blocker 5. I am running Chrome with an ad blocker (same ad blocker in Fifefox) 6. I am running Firefox to the latest version (Firefox 119.0.1 (20231106151204))

What I've done so far: 1. Cleared caches and data. 2. Updated my Windows to the latest update available - Win10 v.22H2 3. Signed-out of Spotify for all my devices, then logging-in first on Spotify Desktop (this automatically redirects to Firefox webplayer) 4. Ran Firefox on "Troubleshoot Mode" 5. Un-checked and re-checked "Play DRM content" setting. 6. Disabled and re-enabled the plug-in "Widevine Content Decryption Module by Google Inc". (this plug-in is last udpated on November 17, 4.10.2710.0

I'm including this link from Spotify's Community page.. where two other users, who commented it is only with Firefox (webplayer), are experiencing the same problem as I am. https://community.spotify.com/t5/Desktop-Windows/Spotify-can-t-play-this-right-now-If-you-have-the-file-on-your/m-p/5679914#M123192

Hello, Firefox won't save my download history between sessions, history is set to remember. I tried doing the refresh on the installer and even reinstalling firefox and deleting all mozilla folders in %localappdata% and %appdata% before reinstalling. it just forgets all downloads once I close firefox.

Video Link

The bookmarks on my taskbar are all of a sudden not showing up. I'm unable to drag them there like I used to. Also, the history and menu button on the upper right don't work now. I've restarted with no luck.