If you're using mozilla.cfg, you can do this.

My best pointer to how to do this would be to look at how the CCK2 does it:

https://github.com/mkaply/cck2wizard/blob/master/cck2/modules/CCK2.jsm#L761

You bascially have to do an XMLHttprequest to the site and intercept the request.

Hey Mike,

thanks a lot for the suggestion! To be honest though I don't fully understand how I would implement it. I think you already pointed out the correct line of code but unfortunately I don't really get how and where I would implement a XMLHttprequest, In a file? I looked through this article here: https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest however I'm still not sure how to proceed.

Thanks again!

That's fine. What do your autoconfig files like today? Would you be willing to send one to mkaply at mozilla.com and I'll add the code for you?

Hey Mike,

that is a very generous offer I would happily take you up on it. Though my lack of Firefox configuration knowledge now comes to the surface. By autoconfig file you mean the policies.js? I had a quick read here: https://support.mozilla.org/en-US/kb/customizing-firefox-using-autoconfig and it doesn't even seem like we have the autoconfig.js in place. We do however seem to have a lot of configurations listed in the autoconfig article within the "Mozilla.cfg" so do you want me to provide you with that file? In case that is true I would have to remove some preference containing internal URLS but I think I'd be able to provide you with the file. The policies.js as well as local-settings.js both seem to point to the mozilla.cfg

Local-settings.js: pref("general.config.obscure_value", 0); pref("general.config.filename", "mozilla.cfg");

policies.js: pref("general.config.obscure_value", 0); pref("general.config.filename", "mozilla.cfg");

Thats all the content of those files.

My apologies for the lack of knowledge in that regard.

Thanks again!

Actually I need the mozilla.cfg file. It might have sensitive info in it, so you might want to email it to me.

Hey Mike,

i have sent you the file via mail.

Thanks a lot!

Hi,

Mike was able to solve this issue through the XML Http request. Here is the solution(not sure if there is a better way to post code here, hope this works):

Cu.importGlobalProperties(["XMLHttpRequest", "URL"]);

let overrides = ["self-signed.badssl.com"]

let setOverrides; try {

 setOverrides = getPref("setOverrides").split(",");

} catch (e) {} if (setOverrides != overrides) {

 Services.obs.addObserver(function observer() {
   let overrideService = Cc["@mozilla.org/security/certoverride;1"].getService(
     Ci.nsICertOverrideService
   );
   for (var i=0; i < overrides.length; i++) {
     let xhr = new XMLHttpRequest();
     try {        
       xhr.open("GET", "https://" + overrides[i]);
       xhr.onerror = function() {
         if (xhr.channel && xhr.channel.securityInfo) {
           let secInfo = xhr.channel.securityInfo.QueryInterface(Ci.nsITransportSecurityInfo);
           let cert = secInfo ? secInfo.serverCert : null;
           if (cert) {
             let url = new URL(xhr.responseURL);
             let flags = 0;
             flags |= overrideService.ERROR_UNTRUSTED;
             overrideService.rememberValidityOverride(
             url.hostname,
             443,
             cert,
             flags,
             false);
           }
         }
       }
       xhr.send(null);
     } catch (ex) {}
   }
   pref("setOverrides", overrides.join(","));
   Services.obs.removeObserver(observer, "final-ui-startup");
 }, "final-ui-startup");

}

You can add multiple domains as well.

All credits go to Mike, thank you again!

Note this solution was for Firefox 69 ESR. I didn't test if it works on current Firefox (but it should).

Might need small changes when ESR 78 comes out.