On a fresh install of Kubuntu 24.04 LTS, the Linux online installer takes a very long time to fail when retrieving information from remote repositories and the failure message recommends a "Windows" URL for finding a different mirror.

I attached screenshots showing progress, and final failure screen.

The process took about 45 minutes to fail. Most time was spent in the "Retrieving information from remote repositories" screen, and then perhaps 5 minutes on the "Retrieving meta information from remote repository..." screen before giving the error message.

The error message recommends finding a list of available mirrors at: "[https://download.qt.io/online/qtsdkrepository/windows_x86/root/qt/Updates.xml.mirrorlist]" which is odd because of "windows_x86" in the middle of the URL.

The instructions with the error message are confusing. The instruction on how to find an appropriate mirror gives a URL and recommends to "use the path before /online", which if obeyed yields only "downloads.qt.io", which does not have any links to repositories.