speedofanimals.com is an example. With HTTPS-Only Mode enabled, if I enter
in the address bar then we experience a long timeout (90s). But if I enter
then it upgrades to https://www.speedofanimals.com and the site immediately loads.
Here's an idea to fix this problem: if the browser is trying to load an HTTP URL with domain "foo.example" and that is failing to upgrade, could we try "https://www.foo.example/..." in the background?
(This behavior could be controlled by the existing prefs