user_pref("general.useragent.updates.enabled", true);
user_pref("gfx.compositor.external-window", true);
user_pref("gfx.compositor.clear-context", false);
user_pref("embedlite.compositor.external_gl_context", true);

user_pref("general.useragent.updates.enabled", true);
user_pref("gfx.compositor.external-window", true);
user_pref("gfx.compositor.clear-context", false);
user_pref("embedlite.compositor.external_gl_context", true);
user_pref("apz.allow_zooming", true);
user_pref("dom.meta-viewport.enabled", true);

Fix default preferences