XnView Software

Using XnView MP Windows Version 0.93.1 64bits (Mar 6 2019).
This bug is related to another reported bug posted here https://newsgroup.xnview.com/viewtopic.php?f=62&t=39128.
I want to display categories under each thumbnail, so I tried to set up two custom labels from (Settings --> Browser -> Thumbnail) i.e.
Custom 3: {IPTC:Category}
Custom 4: {IPTC:Sup. Category}

but the browser is unable to show any such categories. Please note that in the given screenshot categories assigned to an image can be seen in categories panel (Green Block), but not under any thumbnail, instead, there are blank lines (Red Blocks). Please see attached screenshot:
In addition, the tooltip or popup information box is also unable to display much information including our Custom labels: I would like to display my assigned categories with each thumbnail which helps a lot to organize the images in so many ways.
Please correct it or guide towards some workaround.
Thanks a bunch.

"IPTC categories" is not the same thing as "XnViewMp's categories"

IPTC categoy is an (old) metadata you can edit only with "Edit iptc/xmp" window. I think no one uses this metadata anymore.

"XnViewMp's categories" is a tool that one can use to enter keywords in photos and update internal database. (file xnview.db)
Depending on metadata settings you've chosen, this wil create/update IPTC Keywords, and/or XMP Subject + XMP:Lr:Hierarchical Keywords ...

XnviewMp is able to display only "IPTC Keywords" under thumbnails . Can't display Xmp metadata here.

Thank for the reply.
So there is no way to display XnviewMP's category here. That's what my target was...

In Settings, (Browser) Thumbnails, Overlay Icons, if "has keywords" is checked, a yellow icon will be displayed on thumbnails having a category.

The only other way is to enable writing IPTC keywords (for jpg pictures), and display this label...

To quote Michael 038:
"IPTC category is an (old) metadata [..] I think no one uses this metadata anymore."
[..]
"XnviewMp is able to display only "IPTC Keywords" under thumbnails . Can't display Xmp metadata here."

Sooo, XnViewMP can create (new) XMP keywords/tags, but can only display the (old) IPTC keywords/tags in the thumbnail view.
That does not make any sense whatsoever.

Most experts have been saying that IPTC is obsolete for over 10 years.
It makes sense to keep iptc for compatibility, but it's true that Xnviewmp is late in offering XMP metadata in all menus and settings by default.
That needs work and courage for the (only) developer

And some other software are still unable to handle xmp in 2023 at all...