Hi, "Internet Sharing" in system preference is a macOS feature that is completely separate from Firefox Sync.

Are you trying to disable Firefox Sync? If so, could you try the instructions in the following article and see if they help: Disable Firefox Sync

If you're trying to disable syncing on your icloud account, the best place to ask is Apple Support - https://support.apple.com/

Hi Chris.

Thanks for your quick reply.

Yes, I realize they are separate. I've followed the disabled Firefox sync per the instructions (I'm trying to upload a screen shot of that page - but it doesn't seem to want to upload :). Anyway, in Firefox preferences on the Sync tab, it shows that I need to sign into Sync. So I would assume that they shouldn't be syncing unless I'm signed in to sync.

That said, maybe it is an icloud issue. I'll try that route and let you know what happens.

Thank you!