Bug 1654325 - disable the parent process slow script dialog, r=esmyth

Differential Revision: https://phabricator.services.mozilla.com/D84396

modules/libpref/init/all.js

@@ -2426,7 +2426,7 @@ pref("editor.resizing.preserve_ratio",       true);
 pref("editor.positioning.offset",            0);
 
 pref("dom.use_watchdog", true);
-pref("dom.max_chrome_script_run_time", 20);
+pref("dom.max_chrome_script_run_time", 0);
 pref("dom.max_script_run_time", 10);
 pref("dom.max_ext_content_script_run_time", 5);