Just a question: a previous reviewer mentioned that it was necessary to define "dom.webcomponents.shadowdom.enabled" as true in about:config... I'd like to know more about this, since the plug-in works well even without that property being set.
If you are using Firefox version 62 and below, then enabling dom.webcomponents.shadowdom.enabled in about:config was required, in version 63 and above Shadow DOM is enabled by default, so this is not required.
