Fully reviewed & signed, but install rejected

My self-distributed add on has passed full review and is signed but when I try to install it I receive “Firefox prevented this site from asking you to install software on your computer.”

https://addons.mozilla.org/en-US/developers/addon/turbodial-linker-infusionsoft/versions

How can I make it pass the installation checks?

The error comes when I link to a copy of the extension that is hosted on my website. Is that not allowed? Do I have to resort to drag & drop for the install?

Is that file really downloaded from addons.mozilla.org? BTW, I can’t see the page.

No, it’s unlisted and self-distributed. Only mozilla staff and I should be able to see the page.
I put the signed extension on my website with a link for downloading, and clicking that link causes the error message in FF.

This add-on has been deleted.

Yes, I’ve concluded that the “unlisted” approach won’t lead to a good experience for my Users - too many barriers to installation. So, to switch to “listed” i had to delete the add-on and start over. The new version has now been submitted for full review.
This topic can be closed.
Thanks.