"*": {
   "blocked_install_message": "Custom error message.",
   "install_sources": ["https://yourwebsite.com/*"],
   "installation_mode": "blocked",
   "allowed_types": ["extension"]
 },
 "uBlock0@raymondhill.net": {
   "installation_mode": "force_installed",
   "install_url": "https://addons.mozilla.org/firefox/downloads/latest/ublock-origin/latest.xpi"
 },
   "https-everywhere@eff.org": {
   "installation_mode": "allowed"
 }

Hi All, We need to manage Firefox extension based on this mozilla documentation https://github.com/mozilla/policy-templates#extensionsettings in gpo it is working as expected. in Intune https://github.com/mozilla/policy-templates#windows-intune-50 OMA-URI: ./Device/Vendor/MSFT/Policy/Config/Firefox~Policy~firefox~Extensions/ExtensionSettings Value (string): <enabled/> <data id="ExtensionSettings" value=' { "*": { "blocked_install_message": "Custom error message.", "install_sources": ["https://yourwebsite.com/*"], "installation_mode": "blocked", "allowed_types": ["extension"] }, "uBlock0@raymondhill.net": { "installation_mode": "force_installed", "install_url": "https://addons.mozilla.org/firefox/downloads/latest/ublock-origin/latest.xpi" }, "https-everywhere@eff.org": { "installation_mode": "allowed" } }'/> it is not working. event log shows: MDM ConfigurationManager: Command failure status. Configuration Source ID: (A99D19EE-CBD9-4A8B-8831-06E2299A3D22), Enrollment Name: (MDMDeviceWithAAD), Provider Name: (Policy), Command Type: (Add: from Replace or Add), CSP URI: (./Device/Vendor/MSFT/Policy/Config/Firefox~Policy~firefox~Extensions/ExtensionSettings), Result: (The system cannot find the file specified.). Can you help me with this, please? Thank you Michael