Describe the bug
The proxy is unable to generate a valid certificate for domains with Second Level Domains. Websites like https://tfl.gov.uk/ do not generate a valid certificate, because a wildcard domain for *.gov.uk or other domains are not allowed by browsers.

Because of HSTS, this error breaks the website completely if the proxy is used.

Describe the tool and the environment
I used Fluxzy.Desktop just with a custom root certificate on Windows 11. After that I used the proxy systemwide.

To Reproduce

• Setup custom root certificate in Fluxzy.Desktop
• Enable Proxy in Windows Settings and pointed it to Fluxzy.Desktop.
• Restarted Chrome
• Visit https://www.tripadvisor.co.uk/ -> Works, Certificate is accepted
• Visit https://www.gov.uk/ -> Works, Certificate is accepted
• Visit https://tfl.gov.uk/ -> Error net::ERR_CERT_COMMON_NAME_INVALID appears.

Screenshot

(Ignore the "Issuer" value, this is set by me)

Expected behavior
I expected the page to behave exactly like the other websites listed. The Certificate should be accepted by the browser.

Additional context
I used Chrome 135.