Firefox for Enterprise Isithangami Sokwesekwa

Multiple banks are removing Firefox due to vulnerabilities. They have found as I have told them multiple times that there is no centralized method to ensuring firefox remains up to date. The admx files from github do set the appautoupdate and backgroundappupdate to a value of 1 to indicate updates but all PCs are at different levels from 90.0 to 95.0 and I've found that even with the auto update switch on that many pcs do not auto update due to users leaving firefox up and ignoring the restart. The autoupdate task runs only if the user is logged on and that allows users to browse with an insecure version of Firefox that can lead to data breaches. CVEs lead to threats to exploit the CVE and that leads to risk that leads to data breaches. These CVEs are tracked by the NVD and this puts security in the hands of users instead of the business and the business has decided to remove firefox from their environments due to this fact.

I know mozilla is NFP but to maintain firefox in an enterprise environment, it need a better update process such as Google Chrome and Edge Chromium.

CVE-2021-38503 CVE-2021-38504 CVE-2021-38505 CVE-2021-38506 CVE-2021-38507 CVE-2021-38508 CVE-2021-38509 CVE-2021-38510

The above are current CVEs of High risk in one environment that has decided firefox will no longer be used.

I downloaded the admx files for Mozilla Firefox and put them in with the other Windows provided Administrative Local Policy Templates, thinking that it SHOULD show up in the Group Policy Editor tool provided with Windows 10. Apparently I could not have been more wrong. Does anybody know how to make the template show up on a non-domain (Home PC running Windows 10 Pro) computer? Granted, I know I can't control it from "Active Directory" since there is none, but I still want to add this functionality to the PC.

What I have tried: I renamed C:\Windows\PolicyDefinitions to C:\Windows\PolicyDefinitions.old I then Reopened GPEditor and verified all templates had been cleared of viewing (Empty set). I then created a new folder called C:\Windows\PolicyDefinitions and copied the files into it. It refuses to read the Firefox, but everything else shows back up. I downloaded the files again, and reinstalled them, but it still does not show up. I then Rebooted the PC, but my attempts were futile. Any assistance would be appreciated.

Hello

I'm Bae, and i'm sorry for my poor English.

I want to make my users be able to use seamless single sign on to Microsoft Azure by setting Firefox config with Active Directory group policy.

First, I created the 'user.js' file and wrote 'user_pref("network.negotiate-auth.trusted-uris","https://autologon.microsoftazuread-sso.com");' and 'user_pref("network.negotiate-auth.delegation-uris","https://autologon.microsoftazuread-sso.com");' in it.

Second, I put this user.js file in the Firefox¥Profiles folder (such as xxx.default-release).

Third, I checked that the setting was changed on about:config.

Last, I also checked that I could use seamless single sign on to "www.office.com".

What I want to do is to distribute this user.js file to my domain users (exactly, to users' firefox profiles folder) by group policy. Please tell me how to do.

Or, if there is any way to set 'network.negotiate-auth.trusted-uris' and 'network.negotiate-auth.delegation-uris' without user.js file, such as Firefox group policy template, please tell me which one I should modify.

Thanks.

I make the Mendeley Firefox plugin available to managed windows 10 workstations by downloading the plugin file to this location on a workstation:

C:\Program Files (x86)\Mendeley Desktop\Firefox Importer\mendeley_web_importer-3.2.65-fx.xpi

and then add a registry setting to the machine as follows:

[HKEY_LOCAL_MACHINE\SOFTWARE\Mozilla\Firefox\Extensions] "@mendeleyimporter"="C:\\Program Files (x86)\\Mendeley Desktop\\Firefox Importer\\mendeley_web_importer-3.2.65-fx.xpi"

This method worked for previous versions of Firefox and Mendeley Importer, but for the latest versions of both the plugin no longer appears in Firefox.

No error messages are generated.

Is this method still supported by Firefox?

Thanks Mike

We block our user's access to about:config in Firefox for security reasons. I need to set the browser.cache.disk.capacity and browser.cache.disk.max_entry_size for a group of users as recommended by an online services provider. Those values are not available under the preferences policy in the ADMX template for Firefox. How can I set these values in group policy? Is there a registry entry I can make? I tried changing them on my computer and then finding the change in the registry but was unable to find the changed values.

Hi,

I'm trying to auto enable 2 extensions for my users, and after hours on the issue, I cannot find any fix.

We are using: ESR 91.4 32 bits

I've tried to use: - Group Policy -> ExtensionSettings {

 "policies": {
   "ExtensionSettings": {

"uBlock0@asipsante.fr": { "installation_mode": "force_installed", "install_url": "file:///c:/Program Files (x86)/Ivanti/Workspace Control/Data/DBCache/Resources/custom_resources/Logiciels/Mozilla/extensions/CPS2ter-2020_Firefox@asipsante.fr.xpi" }, "uBlock1@netsoins.org": { "installation_mode": "force_installed", "install_url": "https://maintenance.netsoins.org/cpsvitale/firefox.xpi" } } } }

- and Registry HKCU\Software\Policies\Mozilla\Firefox -> ExtensionSettings (REG_MULTI_SZ): { "uBlock0@asipsante.fr": { "installation_mode": "force_installed", "install_url": "file:///c:/Program Files (x86)/Ivanti/Workspace Control/Data/DBCache/Resources/custom_resources/Logiciels/Mozilla/extensions/CPS2ter-2020_Firefox@asipsante.fr.xpi" }, "uBlock1@netsoins.org": { "installation_mode": "force_installed", "install_url": "https://maintenance.netsoins.org/cpsvitale/firefox.xpi" } }

-> HKCU\Software\Policies\Mozilla\Firefox\Extensions\Install 1 (REG_SZ): c:\Program Files (x86)\Ivanti\Workspace Control\Data\DBCache\Resources\custom_resources\Logiciels\Mozilla\extensions\CPS2ter-2020_Firefox@asipsante.fr.xpi 2 (REG_SZ): https://maintenance.netsoins.org/cpsvitale/firefox.xpi

The result is: extension are installed, but always disabled. I have to manually enable them.

Would you have any idea?

thanks for help

i am switching preference / policy management from the mozilla.cfg file to the admin template/GPO. i need to know if the following are still supported in the current release of Firefox ESR.

lockPref("app.update.enabled", false); lockPref("browser.download.dir", "N:"); lockPref("browser.download.downloadDir", "N:"); lockPref("browser.shell.checkDefaultBrowser", false); lockPref("dom.disable_open_during_load", true); lockPref("privacy.item.history", false); lockPref("xpinstall.whitelist.required", true); lockPref("browser.newtabpage.activity-stream.feeds.section.highlights", false); lockPref("browser.newtabpage.activity-stream.feeds.section.topstories", false); lockPref("browser.urlbar.autocomplete.enabled", false); lockPref("network.automatic-ntlm-auth.allow-non-fqdn", true); lockPref("plugin.default_plugin_disabled", "PDF, FDF, XFDF, LSL, LSO, LSS, IQY, RQY, XLK, XLS, XLT, POT, PPS, PPT, DOS, DOT, WKS, BAT, PS, EPS, WCH, WCM, WB1, WB3, RTF, DOC, MDB, MDE, WBK, WB1, WCH, WCM, AD, ADP"); lockPref("privacy.sanitize.promptOnSanitize", false); lockPref("privacy.sanitize.timeSpan", 40); lockPref("security.enable_ssl2", false); lockPref("security.enable_ssl3", false); lockPref("startup.homepage_welcome_url", ""); lockPref("startup.homepage_welcome_url.additional", ""); lockPref("toolkit.crashreporter.enabled", false);

if they are no longer supported, i need to know when (which release) they became unsupported. if there is a link that details all afailable preference and their support status, please provide that as well.

Thanks in advance.

I know users are allow to disable http3 through "about:config", and it works.

However, I have to apply to multiple devices by script and the risk page might be a challenge for me.

I tried to edit prefs.js, but it will still be overwrite even I restart my device. (Re-install is not allowed)

Is there any alternative way to disable http3, such as regedit key?

Or is there method to keep pref.js unchangeable?

Hello Team,

We are trying to disable DoH option in firefox, but i am still not able to disable it using plist file. If anyone can help with the plist file and location to put the file in MacOS it would be a great help.

I am using the below plist file <plist> <dict> <key>DNSOverHTTPS</key> <dict> <key>Enabled</key> <false/> <key>Locked</key> <true/> </dict> </dict> </plist> Ref: https://github.com/mozilla/policy-templates/blob/master/README.md

Thanks

Hey! We want to use Firefox in our school. The school computers are running Windows 10 in a domain. The normal users don´t have rights to install software / updates. That's why we want to use the Mozilla Maintenance Service but it doesn´t work as expected.

After installing a clean Firefox (no old profiles, data, or anything else) it shows that there is a new version. When you click on that message you have to get through Windows UAC. With the admin it is just a "yes"-click but everyone else needs a password.

Any ideas what i can check or try to get the Mozilla Maintenance Service updating Firefox?

Thanks a lot! Nils

Trying to block all but allow specific plugins. I have the okta one and the web password filler working, but not the logon assist. I've tried putting in (secret-server-logon-assist-ff57@thycotic.com), and {secret-server-logon-assist-ff57@thycotic.com}, and also without any extras. These codes come from just the numeric URL (ie https://addons.mozilla.org/firefox/downloads/file/1747490) which says "Secret Server Login Assist (secret-server-logon-assist-ff57@thycotic.com) is blocked by your system administrator. Extension not on OAI allowed list". Am I misreading this message, or missing something on this specific one?

{ "*": { "blocked_install_message" : "Extension not on OAI allowed list", "installation_mode": "blocked" }, "dd1e31d5-3623-45cb-b1ad-64074d36b360@thycotic.com": { "installation_mode": "allowed", "install_url": "https://addons.mozilla.org/firefox/downloads/file/3906662/secret_server_web_password_filler-3.2-fx.xpi" }, "secret-server-logon-assist-ff57@thycotic.com": { "installation_mode": "allowed", "install_url": "https://addons.mozilla.org/firefox/downloads/file/1747490/secret_server_login_assist-2.1.1-an+fx.xpi" }, "plugin@okta.com": { "installation_mode": "allowed", "install_url": "https://addons.mozilla.org/firefox/downloads/file/3901586/okta_browser_plugin-6.8.0-an+fx.xpi" } }

I am looking for a method to be able to programmatically load CA certificates system wide as opposed to a per user method. We made a modification policies.json to install a certificate but it's not working, we followed the documentation on Github

https://github.com/mozilla/policy-templates/blob/master/README.md

Attached is the screenshot of the section we used.

Every time Firefox is opened it gives an error message (see image).

I have tried:

• Deleting and reinstalling.
• Deleting Firefox folder in //users/xxxxxxx/Library/Application Support & //Library/Caches then uninstalling Firefox.
• Both above using older Firefox versions.

This issue is happening on all of the Macs in our org. We have no custom configurations. The pkg is installed via FileWave device management. It occurs whether installed through FileWave or manually.

Thanks

Is there a global way to turn off dns over https and also make firefox use the system certificate store?

We have a dns filter that needs to resolve all dns querys and we need a certificate on all systems to allow our Fortigate to do deep packed inspection on all traffic including encrypted.

I am struggling to find the right policy for disabling "basic authentication" in Firefox using GPO or Intune policy. For other chromium browser like Chrome and Edge Chromium is very straightforward.

Been struggling to find right config or policies. Non of about:config or about:policy seems to work.

Please suggest.

Regards, Rakesh

Hello, I am trying to customize the Firefox Homepage XML file and need some assistance as to what fields need to modified with the url to set the default homepage. Please let me know if you have any questions. Thanks

<plist version="1.0"> <dict> <key>EnterprisePoliciesEnabled</key> <true/> <key>AllowedDomainsForApps</key> <string>managedfirefox.com,example.com</string> <key>AppAutoUpdate</key> <true/> <key>AppUpdateURL</key> <string>https://www.example.com/update.xml</string> <key>Authentication</key> <dict> <key>SPNEGO</key> <array> <string>mydomain.com</string> <string>https://myotherdomain.com</string> </array> <key>Delegated</key> <array> <string>mydomain.com</string> <string>https://myotherdomain.com</string> </array> <key>NTLM</key> <array> <string>mydomain.com</string> <string>https://myotherdomain.com</string> </array> <key>AllowNonFQDN</key> <dict> <key>SPNEGO</key> <true/> <key>NTLM</key> <true/> </dict> <key>AllowProxies</key> <dict> <key>SPNEGO</key> <true/> <key>NTLM</key> <true/> </dict> <key>PrivateBrowsing</key> <true/> <key>Locked</key> <true/> </dict> <key>AutoLaunchProtocolsFromOrigins</key> <array> <dict> <key>protocol</key> <string>zoommtg</string> <key>allowed_origins</key> <array> <string>https://somesite.zoom.us</string> </array> </dict> </array> <key>BlockAboutAddons</key> <true/> <key>BlockAboutConfig</key> <true/> <key>BlockAboutProfiles</key> <true/> <key>BlockAboutSupport</key> <true/> <key>Bookmarks</key> <array> <dict> <key>Title</key> <string>Example1</string> <key>URL</key> <string>https://www.example.org</string> <key>Favicon</key> <string>https://www.example.org/favicon.ico</string> <key>Placement</key> <string>toolbar</string> <key>Folder</key> <string>Example1Folder</string> </dict> <dict> <key>Title</key> <string>Example2</string> <key>URL</key> <string>https://www.example.com</string> <key>Favicon</key> <string>https://www.example.com/favicon.ico</string> <key>Placement</key> <string>menu</string> <key>Folder</key> <string>Example2Folder</string> </dict> </array> <key>CaptivePortal</key> <false/> <key>Certificates</key> <dict> <key>ImportEnterpriseRoots</key> <true/> <key>Install</key> <array> <string>cert1.der</string> <string>cert2.pem</string> </array> </dict> <key>Cookies</key> <dict> <key>Allow</key> <array> <string>https://www.example.org/</string> </array> <key>Allowsession</key> <array> <string>https://www.example.edu/</string> </array> <key>Block</key> <array> <string>https://www.example.edu/</string> </array> <key>Behavior</key> <string>limit-foreign</string> <key>Locked</key> <true/> </dict> <key>DefaultDownloadDirectory</key> <string>${home}/Downloads</string> <key>DownloadDirectory</key> <string>${home}/Downloads</string> <key>DNSOverHTTPS</key> <dict> <key>Enabled</key> <false/> <key>ProviderURL</key> <string>URL_TO_ALTERNATE_PROVIDER</string> <key>Locked</key> <true/> <key>ExcludedDomains</key> <array> <string>example.com</string> </array> </dict> <key>DisableAppUpdate</key> <true/> <key>DisableBuiltinPDFViewer</key> <true/> <key>DisabledCiphers</key> <dict> <key>TLS_DHE_RSA_WITH_AES_128_CBC_SHA</key> <true/> <key>TLS_DHE_RSA_WITH_AES_256_CBC_SHA</key> <true/> <key>TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA</key> <true/> <key>TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA</key> <true/> <key>TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256</key> <true/> <key>TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256</key> <true/> <key>TLS_RSA_WITH_AES_128_CBC_SHA</key> <true/> <key>TLS_RSA_WITH_AES_256_CBC_SHA</key> <true/> <key>TLS_RSA_WITH_3DES_EDE_CBC_SHA</key> <true/> <key>TLS_RSA_WITH_AES_128_GCM_SHA256</key> <false/> <key>TLS_RSA_WITH_AES_256_GCM_SHA384</key> <false/> </dict> <key>DisableDeveloperTools</key> <true/> <key>DisableFeedbackCommands</key> <true/> <key>DisableFirefoxAccounts</key> <true/> <key>DisableFirefoxScreenshots</key> <true/> <key>DisableFirefoxStudies</key> <true/> <key>DisableForgetButton</key> <true/> <key>DisableFormHistory</key> <true/> <key>DisableMasterPasswordCreation</key> <true/> <key>DisablePasswordReveal</key> <true/> <key>DisablePocket</key> <true/> <key>DisablePrivateBrowsing</key> <true/> <key>DisableProfileImport</key> <true/> <key>DisableProfileRefresh</key> <true/> <key>DisableSafeMode</key> <true/> <key>DisableSecurityBypass</key> <dict> <key>InvalidCertificate</key> <true/> <key>SafeBrowsing</key> <true/> </dict> <key>DisableSetDesktopBackground</key> <true/> <key>DisableSystemAddonUpdate</key> <true/> <key>DisableTelemetry</key> <true/> <key>DisplayBookmarksToolbar</key> <true/> <key>DontCheckDefaultBrowser</key> <true/> <key>EnableTrackingProtection</key> <dict> <key>Value</key> <true/> <key>Locked</key> <true/> <key>Cryptomining</key> <true/> <key>Fingerprinting</key> <true/> <key>Exceptions</key> <array> <string>https://example.com</string> </array> </dict> <key>EncryptedMediaExtensions</key> <dict> <key>Enabled</key> <false/> <key>Locked</key> <false/> </dict> <key>Extensions</key> <dict> <key>Install</key> <array> <string>https://addons.mozilla.org/firefox/downloads/file/1053714/ghostery_privacy_ad_blocker-8.2.4-an+fx.xpi</string> </array> <key>Uninstall</key> <array/> <key>Locked</key> <array> <string>firefox@ghostery.com</string> </array> </dict> <key>ExtensionSettings</key> <dict> <key>*</key> <dict> <key>blocked_install_message</key> <string>Custom error message.</string> <key>install_sources</key> <array> <string>https://addons.mozilla.org/</string> </array> <key>installation_mode</key> <string>blocked</string> </dict> <key>uBlock0@raymondhill.net</key> <dict> <key>installation_mode</key> <string>force_installed</string> <key>install_url</key> <string>https://addons.mozilla.org/firefox/downloads/latest/ublock-origin/latest.xpi</string> </dict> </dict> <key>ExtensionUpdate</key> <false/> <key>FirefoxHome</key> <dict> <key>Search</key> <true/> <key>TopSites</key> <true/> <key>SponsoredTopSites</key> <false/> <key>Highlights</key> <true/> <key>Pocket</key> <false/> <key>SponsoredPocket</key> <false/> <key>Snippets</key> <false/> <key>Locked</key> <true/> </dict> <key>FlashPlugin</key> <dict> <key>Allow</key> <array> <string>https://www.example.com</string> </array> <key>Block</key> <array> <string>https://www.example.org</string> </array> <key>Default</key> <true/> <key>Locked</key> <true/> </dict> <key>Handlers</key> <dict> <key>mimeTypes</key> <dict> <key>application/msword</key> <dict> <key>action</key> <string>useSystemDefault</string> <key>ask</key> <false/> </dict> </dict> <key>schemes</key> <dict> <key>mailto</key> <dict> <key>action</key> <string>useHelperApp</string> <key>ask</key> <false/> <key>handlers</key> <array> <dict> <key>name</key> <string>Gmail</string> <key>uriTemplate</key> <string>https://mail.google.com/mail/?extsrc=mailto&url=%s</string> </dict> </array> </dict> </dict> <key>extensions</key> <dict> <key>pdf</key> <dict> <key>action</key> <string>useHelperApp</string> <key>ask</key> <false/> <key>handlers</key> <array> <dict> <key>name</key> <string>Adobe Acrobat</string> <key>path</key> <string>/System/Applications/Preview.app</string> </dict> </array> </dict> </dict> </dict> <key>HardwareAcceleration</key> <false/> <key>Homepage</key> <dict> <key>URL</key> <string>http://example.com</string> <key>Locked</key> <true/> <key>Additional</key> <array> <string>https://www.example.com/extra-home1.htm</string> <string>https://www.example.com/extra-home2.htm</string> <string>https://www.example.com/extra-home3.htm</string> </array> <key>StartPage</key> <string>homepage</string> </dict> <key>InstallAddonsPermission</key> <dict> <key>Allow</key> <array> <string>https://example.org</string> <string>https://example.edu</string> </array> <key>Default</key> <false/> </dict> <key>LocalFileLinks</key> <array> <string>http://example.org</string> <string>http://example.edu</string> </array> <key>PrimaryPassword</key> <true/> <key>NetworkPrediction</key> <false/> <key>NewTabPage</key> <false/> <key>NoDefaultBookmarks</key> <true/> <key>OfferToSaveLogins</key> <false/> <key>OfferToSaveLoginsDefault</key> <true/> <key>OverrideFirstRunPage</key> <string>https://www.example.com</string> <key>OverridePostUpdatePage</key> <string></string> <key>PasswordManagerEnabled</key> <false/> <key>PDFjs</key> <dict> <key>Enabled</key> <false/> <key>EnablePermissions</key> <false/> </dict> <key>Permissions</key> <dict> <key>Camera</key> <dict> <key>Allow</key> <array> <string>https://example.org</string> </array> <key>Block</key> <array> <string>https://example.edu</string> </array> <key>BlockNewRequests</key> <true/> <key>Locked</key> <true/> </dict> <key>Microphone</key> <dict> <key>Allow</key> <array> <string>https://example.org</string> </array> <key>Block</key> <array> <string>https://example.edu</string> </array> <key>BlockNewRequests</key> <true/> <key>Locked</key> <true/> </dict> <key>Location</key> <dict> <key>Allow</key> <array> <string>https://example.org</string> </array> <key>Block</key> <array> <string>https://example.edu</string> </array> <key>BlockNewRequests</key> <true/> <key>Locked</key> <true/> </dict> <key>Notifications</key> <dict> <key>Allow</key> <array> <string>https://example.org</string> </array> <key>Block</key> <array> <string>https://example.edu</string> </array> <key>BlockNewRequests</key> <true/> <key>Locked</key> <true/> </dict> <key>Autoplay</key> <dict> <key>Allow</key> <array> <string>https://example.org</string> </array> <key>Block</key> <array> <string>https://example.edu</string> </array> <key>Default</key> <string>block-audio</string> <key>Locked</key> <true/> </dict> <key>VirtualReality</key> <dict> <key>Allow</key> <array> <string>https://example.org</string> </array> <key>Block</key> <array> <string>https://example.edu</string> </array> <key>BlockNewRequests</key> <true/> <key>Locked</key> <true/> </dict> </dict> <key>PictureInPicture</key> <dict> <key>Enabled</key> <false/> <key>Locked</key> <true/> </dict> <key>PopupBlocking</key> <dict> <key>Allow</key> <array> <string>https://www.example.org</string> <string>https://www.example.edu</string> </array> <key>Default</key> <true/> <key>Locked</key> <true/> </dict> <key>Preferences</key> <dict> <key>accessibility.force_disabled</key> <dict> <key>Value</key> <integer>1</integer> <key>Status</key> <string>default</string> </dict> <key>browser.cache.disk.parent_directory</key> <dict> <key>Value</key> <string>SOME_NATIVE_PATH</string> <key>Status</key> <string>user</string> </dict> <key>browser.tabs.warnOnClose</key> <dict> <key>Value</key> <false/> <key>Status</key> <string>locked</string> </dict> </dict> <key>Proxy</key> <dict> <key>SocksVersion</key> <string>4</string> <key>Mode</key> <string>manual</string> <key>HTTPProxy</key> <string>proxy.example.com:80</string> <key>Locked</key> <true/> </dict> <key>RequestedLocales</key> <array> <string>de</string> <string>en-US</string> </array> <key>SanitizeOnShutdown</key> <true/> <key>SearchBar</key> <string>separate</string> <key>UserMessaging</key> <dict> <key>WhatsNew</key> <false/> <key>ExtensionRecommendations</key> <false/> <key>FeatureRecommendations</key> <false/> <key>UrlbarInterventions</key> <false/> <key>SkipOnboarding</key> <true/> </dict> <key>WebsiteFilter</key> <dict> <key>Block</key> <array> <string><all_urls></string> </array> <key>Exceptions</key> <array> <string>https://www.google.com/*</string> <string>https://www.yahoo.com/*</string> </array> </dict> <key>SecurityDevices</key> <dict> <key>NAME_OF_DEVICE</key> <string>PATH_TO_LIBRARY_FOR_DEVICE</string> </dict> <key>ShowHomeButton</key> <true/> <key>SSLVersionMin</key> <string>tls1.2</string> <key>SSLVersionMax</key> <string>tls1.3</string> <key>SupportMenu</key> <dict> <key>Title</key> <string>Click here for help</string> <key>URL</key> <string>http://example.edu/</string> <key>AccessKey</key> <string>C</string> </dict> </dict> </plist>

Launch Firefox, manually check for latest update by going to settings > Help > About Firefox. However the manual update keep showing update failed. Other than Mozilla config file, can we use GPO to configure auto update for Firefox browser?

Launch Firefox, manually check for latest update by going to settings > Help > About Firefox. However the manual update keep showing update failed. Other than Mozilla config file, can we use GPO to configure auto update for Firefox browser?

All our Firefox browsers (version 99.*, Windows 10 Pro or Enterprise) in the company need around 20 seconds to load a web page when first opened. All other browser functions work fluently from the beginning. Also the slowness only happens after opening and not during further use. Which Firefox is refusing to load I can open other tabs and e.g. do a Google search and then the "slowness timer" starts again (independently if the first tab is closed or stays open) and refuses to do anything on that tab. Once the slownedd period is over all tabs are loaded and no further problem occurs. This issue occurs only when the GPO "URL for Home Page" is applied. But this page is reachable and when Firefox is working it loads within milliseconds. For testing I created a new profile and on the first startup the problem already occurs. And all other startups too. When temporarily removing this one GPO entry it immediately works again fluently. It also doesn't matter what I set as home page (company internal website or some random web page); it is always slow once this setting is in place.