fixup! Firefox preference overrides.

Bug 40147: Re-enable Picture-in-Picture mode.

Media capabilities are already protected by RFP.

browser/app/profile/001-base-profile.js

@@ -414,7 +414,6 @@ pref("dom.netinfo.enabled", false);
 pref("network.http.referer.defaultPolicy", 2); // Bug 32948: Make referer behavior consistent regardless of private browing mode status
 pref("network.http.referer.defaultPolicy.pbmode", 2);
 pref("network.http.referer.XOriginTrimmingPolicy", 2); // Bug 17228: Force trim referer to scheme+host+port in cross-origin requests
-pref("media.videocontrols.picture-in-picture.enabled", false); // Bug 40148: disable until audited in #40147
 // Bug 40463: Disable Windows SSO
 pref("network.http.windows-sso.enabled", false, locked);
 // tor-browser#40424