Search for Mimetypes is broken
Let' say you right-click on a XML file in Nautilus and select "Open with other Application". In the Dialog you select "Find new Applications". Gnome Software will open and you see this:
As you can see, it opens Gnome Software with the Mimetype as Searchterm. But it does not find Applications.
Here is Discover, started with plasma-discover --mime application/xml
as comparison:
As you can see, there are far more Apps.
If you run appstreamcli what-provides mediatype application/xml
you will get a list with all App shich provides this Mimetype. It has over 200 Lines, so I will not post it here. All Apps that showed up in Disover are in this list.
I would suggest that yu are add a --mime option like Discover which shows a List of all Apps that provide this Mimetype and use this Option in Nautilus. This is far better than just open a normal Search.
This Problem happens of course with other Mimetypes too and not only application/xml.