Absolute FQDN prevent connection due SSL "Secure Connection Failed".

[RokeJulianLockhart]

Current behavior

Like https://github.com/traefik/traefik/issues/9157#issue-1292092577 describes, if I access the absolute FQDN - https://string.is./ - instead of the relative FQDN - https://string.is/ - I see https://support.mozilla.org/en-US/kb/secure-connection-failed-firefox-did-not-connect?as=u&utm_source=inproduct:

An error occurred during a connection to string.is..

• The page you are trying to view cannot be shown because the authenticity of the received data could not be verified.
• Please contact the web site owners to inform them of this problem.

This hasn't occurred at any other URI thus far.

Expected behavior

I should be able to connect.

Environment

• string-is version: https://github.com/recurser/string-is/releases/tag/v1.37.3 or https://github.com/recurser/string-is/tree/31fdd93cf8c56c591cc142189ca2847e96701eb1, I expect.
• Share link: https://string.is./

I'm using 1.1.1.1 for DNS resolution.