It's currently using collect.kde.org, which is being phased out (software is outdated and we are the only users). Investigation is needed what needs to be done to move the little data we have over there, and then the providers URL needs to be changed in the .knsrc file.
Git commit 44458d9cc234f4b7748fdbbf6178e67be2d343e9 by Friedrich W. H. Kossebau. Committed on 08/11/2019 at 01:01. Pushed by kossebau into branch '5.4'. qthelp: adapt KNewStuff config to move from collect.kde.org to store.kde.org collect.kde.org was shut down recently, as substitute there is now a category at store.kde.org Related: T11415 FIXED-IN:5.4.5 M +2 -2 plugins/qthelp/kdevelop-qthelp.knsrc https://invent.kde.org/kde/kdevelop/commit/44458d9cc234f4b7748fdbbf6178e67be2d343e9