--- a/browser/confvars.sh
+++ b/browser/confvars.sh
@@ -63,7 +63,8 @@
 MOZ_PROFILE_MIGRATOR=1
 
 # Enable checking that add-ons are signed by the trusted root
-MOZ_ADDON_SIGNING=1
+MOZ_ADDON_SIGNING=0
+MOZ_ALLOW_LEGACY_EXTENSIONS=1
 
 # Include the DevTools client, not just the server (which is the default)
 MOZ_DEVTOOLS=all
--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -89,10 +89,10 @@
 #endif
 
 // Extensions that should not be flagged as legacy in about:addons
-pref("extensions.legacy.exceptions", "{972ce4c6-7e08-4474-a285-3208198ce6fd},testpilot@cliqz.com,@testpilot-containers,jid1-NeEaf3sAHdKHPA@jetpack,@activity-streams,pulse@mozilla.com,@testpilot-addon,@min-vid,tabcentertest1@mozilla.com,snoozetabs@mozilla.com,speaktome@mozilla.com,hoverpad@mozilla.com");
+pref("extensions.legacy.exceptions", "");
 
 // Require signed add-ons by default
-pref("xpinstall.signatures.required", true);
+pref("xpinstall.signatures.required", false);
 pref("xpinstall.signatures.devInfoURL", "https://wiki.mozilla.org/Addons/Extension_Signing");
 
 // Dictionary download preference
@@ -1568,7 +1568,7 @@
 pref("extensions.allow-non-mpc-extensions", false);
 #endif
 
-pref("extensions.legacy.enabled", false);
+pref("extensions.legacy.enabled", true);
 
 // Enable blocking of e10s and e10s-multi for add-on users on beta/release.
 #if defined(RELEASE_OR_BETA) && !defined(MOZ_DEV_EDITION)