diff -urN Pale-Moon-27.4.0_Release/browser/app/profile/palemoon.js Pale-Moon-27.4.0_Release-patched/browser/app/profile/palemoon.js
--- Pale-Moon-27.4.0_Release/browser/app/profile/palemoon.js	2017-07-10 22:23:16.000000000 +1000
+++ Pale-Moon-27.4.0_Release-patched/browser/app/profile/palemoon.js	2017-07-13 00:29:16.695614989 +1000
@@ -61,7 +61,8 @@
 
 // Disable add-ons that are not installed by the user in all scopes by default.
 // See the SCOPE constants in AddonManager.jsm for values to use here.
-pref("extensions.autoDisableScopes", 15);
+pref("extensions.autoDisableScopes", 0);
+pref("extensions.showMismatchUI", false);
 
 // Dictionary download preference
 pref("browser.dictionaries.download.url", "https://addons.mozilla.org/%LOCALE%/firefox/dictionaries/");
diff -urN Pale-Moon-27.4.0_Release/toolkit/mozapps/extensions/internal/XPIProvider.jsm Pale-Moon-27.4.0_Release-patched/toolkit/mozapps/extensions/internal/XPIProvider.jsm
--- Pale-Moon-27.4.0_Release/toolkit/mozapps/extensions/internal/XPIProvider.jsm	2017-07-10 22:23:16.000000000 +1000
+++ Pale-Moon-27.4.0_Release-patched/toolkit/mozapps/extensions/internal/XPIProvider.jsm	2017-07-13 00:29:16.877614988 +1000
@@ -2125,11 +2125,9 @@
 
       AddonManagerPrivate.markProviderSafe(this);
 
-      if (aAppChanged === undefined) {
-        // For new profiles we will never need to show the add-on selection UI
-        Services.prefs.setBoolPref(PREF_SHOWN_SELECTION_UI, true);
-      }
-      else if (aAppChanged && !this.allAppGlobal &&
+      // For all profiles we will never need to show the add-on selection UI
+      Services.prefs.setBoolPref(PREF_SHOWN_SELECTION_UI, true);
+      if (aAppChanged && !this.allAppGlobal &&
                Preferences.get(PREF_EM_SHOW_MISMATCH_UI, true)) {
         if (!Preferences.get(PREF_SHOWN_SELECTION_UI, false)) {
           // Flip a flag to indicate that we interrupted startup with an interactive prompt