Bug 1577167 - Enable WS to be on by default in Nightly and Beta. r=Honza

Enable WS to be on by default in Nightly and Beta

Differential Revision: https://phabricator.services.mozilla.com/D43924

--HG--
extra : moz-landing-system : lando

browser/app/profile/firefox.js

@@ -2151,8 +2151,8 @@ pref("devtools.netmonitor.har.forceExport", false);
 pref("devtools.netmonitor.har.pageLoadedTimeout", 1500);
 pref("devtools.netmonitor.har.enableAutoExportToFile", false);
 
-// Enable WebSocket monitoring in Nightly builds.
-#if defined(NIGHTLY_BUILD)
+// Enable WebSocket monitoring in Nightly and DevEdition/Beta builds.
+#if defined(NIGHTLY_BUILD) || defined(MOZ_DEV_EDITION)
   pref("devtools.netmonitor.features.webSockets", true);
 #else
   pref("devtools.netmonitor.features.webSockets", false);