--- a/browser/app/profile/firefox.js
+++ b/browser/app/profile/firefox.js
@@ -669,23 +669,32 @@ pref("accessibility.loadedInLastSession"
 pref("plugins.click_to_play", true);
 pref("plugins.testmode", false);
 
 pref("plugin.default.state", 1);
 
 // Plugins bundled in XPIs are enabled by default.
 pref("plugin.defaultXpi.state", 2);
 
-// Flash is enabled by default, and Java is click-to-activate by default on
-// all channels.
-pref("plugin.state.flash", 2);
+// Java is Click-to-Activate by default on all channels.
 pref("plugin.state.java", 1);
 
+// Flash is Click-to-Activate by default on Nightly,
+// Always-Activate on other channels.
 #ifdef NIGHTLY_BUILD
 pref("plugins.flashBlock.enabled", true);
+pref("plugin.state.flash", 1);
+
+// Prefer HTML5 video over Flash content, and don't
+// load plugin instances with no src declared.
+// These prefs are documented in details on all.js.
+pref("plugins.favorfallback.mode", "follow-ctp");
+pref("plugins.favorfallback.rules", "nosrc,video");
+#else
+pref("plugin.state.flash", 2);
 #endif
 
 #ifdef XP_WIN
 pref("browser.preferences.instantApply", false);
 #else
 pref("browser.preferences.instantApply", true);
 #endif
 

--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -3003,22 +3003,20 @@ pref("idle_queue.min_period", 3);
 // (0 is disabled)
 // Disabled on all platforms per bug 705748 until the found issues are
 // resolved.
 pref("hangmonitor.timeout", 0);
 
 pref("plugins.load_appdir_plugins", false);
 // If true, plugins will be click to play
 pref("plugins.click_to_play", false);
-#ifdef NIGHTLY_BUILD
+
 // This only supports one hidden ctp plugin, edit nsPluginArray.cpp if adding a second
-pref("plugins.navigator.hidden_ctp_plugin", "Shockwave Flash");
-#else
 pref("plugins.navigator.hidden_ctp_plugin", "");
-#endif
+
 // The default value for nsIPluginTag.enabledState (STATE_ENABLED = 2)
 pref("plugin.default.state", 2);
 
 // The MIME type that should bind to legacy java-specific invocations like
 // <applet> and <object data="java:foo">. Setting this to a non-java MIME type
 // is undefined behavior.
 pref("plugin.java.mime", "application/x-java-vm");