STEPS TO REPRODUCE 1. Go to https://apps.kde.org/dolphin 2. Click on "Install on Linux", which opens appstream://org.kde.dolphin and launches Discover OBSERVED RESULT Error message saying "Could not open appstream://org.kde.dolphin because it was not found in any available software repositories. EXPECTED RESULT Dolphin's page opens. ADDITIONAL INFORMATION What's happening is that on my distro (Fedora 37), Dolphin's AppStream URL is appstream://org.kde.dolphin.desktop not appstream://org.kde.dolphin So if I open appstream://org.kde.dolphin.desktop in Discover, it works. Unfortunately the root cause of this issue is messy handling of the .desktop suffix in AppStream itself that's baked in because it's a part of the spec. Because we can't guarantee that the ID on the system and the URL that users open both agree on whether that ".desktop" sufficis present or absent, and we should probably try to handle both.
Looks like we try to; see: - https://invent.kde.org/plasma/discover/-/commit/176db6c331ad1c3bd3f39abf546fd22a659c4f9a - https://invent.kde.org/plasma/discover/-/commit/e1aa6b37f29f54c96d933c1d2372eb24720ddcad but I guess it broke recently or doesn't handle this specific case.
Oh, we removed it in https://invent.kde.org/plasma/discover/-/commit/4ce1e6dca9db1a14437eff90b9e4b67ebe0bb2f3. And I approved the MR removing it. Derp.
Ultimately this turned out to be a bug in the URL generation code on the website that we were working around in Discover! It's now been fixed on the website.