EDIT: Lol, it doesn’t actually work +___+ It is enabled in KeepassXC but it just doesn’t do anything. Welp.
Here’s a neat trick I just found out (with a hint from here):
In Wayland you can’t use KeepassXC’s very cool Auto-Type feature (it’s somehow Qt’s fault?) but if you installed it as a Flatpak you can go into KDE Settings, search for “Flatpak Permission Settings” and in the settings for KeepassXC under “Advanced” you can disable “Wayland Windowing System” to make it work. Nice!
I disagree, I have full trust in the intentions and design capabilities of the Wayland developers. The core of them also developed X.org, after all.
I do agree that there should be some standard way applications should be able to provide accelerators to specific application, but copying things like window titles and X specific APIs is the wrong approach.
Wayland has the Foreign toplevel list protocol to get application IDs for every top level window. I think that API should provide ample capabilities to a password autofill service. It even provides window titles (not useful for matching applications, but very useful for picking default names for newly created entries and audit logs). It doesn’t provide access to windows in the background, but that sounds like a good design decision to me; I can’t think of a reason to password fill a background window.
I absolutely never trust blindly in such things. I have never seen a plausible explanation why this is a security feature.
When there are dev’s from X11 involved, this is fine and it seems that this leads to decisions which prevent from current X11 issues. But it absolutely is no guarantee that everything is trustable. I’m not that expert, but your mentioned link points in the right direction. But as long this isn’t supported in the wide mass, it’s only a wish…