https://qt.io does not work

Requiring www in front of every web site address is an obsolete 1990's habit. It would be best for qt.io to be the actual web site. And some people do expect every web site to be "secure" now, for what it's worth (even though the security has its limitations).

At the very least, the quick fix is to have https://qt.io redirect to https://www.qt.io.

It would be better though to have www.qt.io redirect to qt.io.

This came up while trying to fix the CI problem due to the expired cert on qt-project.org:

https://codereview.qt-project.org/#/c/104619/