Yes it is and that is why you have right to refuse to download. Leave comment with the Developer of he Extension.

Mozilla approves Developers Extensions for use with Firefox and provides a web Page for their Distribution. The Developer does their own Support as there is a link to that and heir is Contact info and a Feedback system for reviews. Also one to report abuses.

Support here only works on them a little and if can and only if it interferes with Firefox.

If you do not like the reasons which are listed why on their web page then do not use the Extension/s.

Happy Surfing.

I see millions of people have downloaded a video downloader, and it seems all of the video downloaders require access to my whole computer. Is that really what's going on?

(Sorry to question your answer - you said it is, but it's so difficult to believe. I just want to make sure I'm understanding you)

See:

• https://support.mozilla.org/en-US/kb/permission-request-messages-firefox-extensions
• https://developer.mozilla.org/en-US/Add-ons/WebExtensions/manifest.json/permissions