Autofill behaviour: Exclude subdomains

I have a similar feature request based on the workaround I use for a situation similar to yours. On my AD domain, let's say example.local, some logins need example\username but others will fail unless it's only username. My workaround has been to use the website autofill behavior custom settings to specify where to use certain sets of credentials. Obviously the drawback is that you need to create multiple entries for the same set of creds.

Anyway, the feature request I have to to adjust the website autofill custom options to include a "use on this domain and all subdomains EXCEPT for X, Y, and Z subdomains." That would help.