OAuth is approved for official builds only

FAQ.md

@@ -3137,7 +3137,9 @@ Therefore you are advised to switch to the GitHub release.
 
 The F-Droid version is built from the same source code, but signed differently.
 This means that all features are available in the F-Droid version too,
-except for using the Gmail quick setup wizard because Google approved (and allows) one signature only.
+except for using the Gmail quick setup wizard because Google approved (and allows) one app signature only.
+For all other email providers, OAuth access is only available in Play Store versions and Github releases,
+as the email providers only permit the use of OAuth for official builds.
 
 Note that you'll need to uninstall the F-Droid build first before you can install a GitHub release
 because Android refuses to install the same app with a different signature for security reasons.

app/src/main/java/eu/faircode/email/FragmentSetup.java

@@ -171,7 +171,6 @@ public class FragmentSetup extends FragmentBase {
                 popupMenu.getMenu().add(Menu.NONE, R.string.title_setup_gmail, order++, R.string.title_setup_gmail);
                 popupMenu.getMenu().add(Menu.NONE, R.string.title_setup_outlook, order++, R.string.title_setup_outlook);
 
-                if (Helper.hasValidFingerprint(getContext()) || BuildConfig.DEBUG)
                 for (EmailProvider provider : EmailProvider.loadProfiles(getContext()))
                     if (provider.oauth != null && provider.oauth.enabled)
                         popupMenu.getMenu()
@@ -206,7 +205,10 @@ public class FragmentSetup extends FragmentBase {
                                 if (item.getIntent() == null)
                                     return false;
                                 else {
+                                    if (Helper.hasValidFingerprint(getContext()) || BuildConfig.DEBUG)
                                         lbm.sendBroadcast(item.getIntent());
+                                    else
+                                        ToastEx.makeText(getContext(), R.string.title_setup_oauth_permission, Toast.LENGTH_LONG).show();
                                     return true;
                                 }
                         }

app/src/main/res/values/strings.xml

@@ -172,6 +172,7 @@
     <string name="title_setup_gmail" translatable="false">Gmail</string>
     <string name="title_setup_outlook" translatable="false">Outlook, Live, Hotmail</string>
     <string name="title_setup_oauth" translatable="false">%1$s (OAuth)</string>
+    <string name="title_setup_oauth_permission">The email provider has approved OAuth only for official app versions</string>
     <string name="title_setup_activesync" translatable="false">Exchange ActiveSync</string>
     <string name="title_setup_other">Other provider</string>
     <string name="title_setup_gmail_support">Authorizing Google accounts will work in official versions only because Android checks the app signature</string>