The .zip TLD recently went live, and so far it does not appear that Firefox makes foo.zip links clickable. However, a future update may add .zip support.
Before you do that, please compliment browser.fixup.domainsuffixwhitelist with browser.fixup.domainsuffixblocklist, and update the AMDX files for enterprise admins.
I was actually surprised to see that the blocklist compliment to whitelist didn’t exist, although looking closer I see that the whitelist exists to solve a slightly different policy (sending unknown TLDs to a search engine, which aside from interfering with local TLDs is likely to fail on a search anyway.)
I see the blocklist as having a slightly different function - preventing that domain suffix from being “clickable” at all, unless prefixed with a protocol such as file:// (or, I guess https://)
The primary value in this is assisting enterprise admins in blocking access directly at the browser, as an additional layer beyond things like DNS black holes - which are made more difficult with DNS over HTTPS enabled on browsers, etc.
More advanced users that can use about:config could also benefit.
I know .zip support probably isn’t coming next week, but just in case - please consider the domainsuffixblocklist if you add support for .zip, .mov, etc.