Some browsers like Firefox are very inflexible with window.open()
and block it if it is not instantly invoked after the user click.
Also according to https://stackoverflow.com/a/6807615 it is best
practice to replace self:: with static::
Fetching the theme version number via get_component_version() which
requires lib/adminlib.php unnecessarily increases memory consumption.
Using get_config() is more direct and simpler.
Jake Dallimore