[Dev] Firefox Sync in Iceweasel not working

[bill-auger]

and another "just to note", avalos found a solution
for the broken "sync" feature

the default config for 'webchannel.allowObject.urlWhitelist'
has only the first 3 URLs below - adding https://accounts.firefox.com
allows the sync feature to work again

what is peculiar though, is that this was allegedly necessary
since firefox v50; but it has been working in iceweasel, without
that URL whitelisted, until only a few versions ago


diff --git a/libre/iceweasel/vendor.js.in b/libre/iceweasel/vendor.js.in
index cccb37aae..1569e9858 100644
--- a/libre/iceweasel/vendor.js.in
+++ b/libre/iceweasel/vendor.js.in
@@ -310,3 +310,6 @@ pref("extensions.getAddons.showPane", false);
 // Setting these preferences just in case and to not frustrate users.
 pref("app.normandy.api_url", "http://127.0.0.1/");
 pref("app.normandy.enabled", false);
+
+// enable "sync" feature
+pref("webchannel.allowObject.urlWhitelist", "https://content.cdn.mozilla.net https://support.mozilla.org https://install.mozilla.org https://accounts.firefox.com");