"policies": {
   "DisableAppUpdate": true,
   "DisablePocket": true,
   "DontCheckDefaultBrowser": true,
   "Homepage": {
     "StartPage": "homepage",
     "URL": "https://www.google.com"
   },
   "PopupBlocking": {
     "Allow": [
       "https://mn.gov",
       "https://state.mn.us"
     ],
     "Default": true
   }
 }

I am trying to update Firefox to 78.2 ESR at my organization as well as change from autoconfig.js and mozilla.cfg based configuration (used in Firefox 68 ESR and earlier) to policies.json based configuration with Firefox 78.x ESR. Update will be deployed via SCCM and a PowerShell script. I have put a policies.json in C:\Program Files\Mozilla Firefox\distrubution\ When I re-install Firefox ESR 78.2 and have the policies.json in place, none of the policies apply. I went so far as to use the Mozilla Firefox Enterprise Policy Generator to make sure the json file is formatted properly. What I have the script doing is uninstalling any old Firefox versions, clearing out the old config files and putting in the policies.json file in C:\Program Files\Mozilla Firefox\distribution\. When I run Firefox after the update, I get an error "Configuration Error: Failed to read the configuration file. Please contact your system administrator." I can click OK on the error and Firefox launches but without any customizations. The error pops up every time I launch Firefox. I am not aware of any Group Policies in place that manage Firefox. Can anyone see a mistake I might be making or something I'm missing in my process? Here is what's in my policies.json file: <code> { "policies": { "DisableAppUpdate": true, "DisablePocket": true, "DontCheckDefaultBrowser": true, "Homepage": { "StartPage": "homepage", "URL": "https://www.google.com" }, "PopupBlocking": { "Allow": [ "https://mn.gov", "https://state.mn.us" ], "Default": true } } } </code>