I may be having a similar issue. Recently I reorganized some of my categories, and now all of my articles are invisible if I open any category in public presentation mode. The articles are still accessible through the codex, but the category pages are completely blank.

Hey simneese,

Can you please let me know in which world and in which categories this happens?

For me, this is occurring in my world:
https://www.worldanvil.com/w/reign-of-dragons-eberg

Every single category is affected. I am wasting significant amounts of time reformatting and re-ordering my categories. This is a constant problem.

Just to update that this is still occurring. Fixed all my category formats, putting the list of pages at the top and hiding Maps, Table of Contents, and Timelines. Checked a couple days later and about a quarter of the ones I checked reverted back to the default again.

Thanks for the update, we are investigating this and will come back to you with any updates as soon as possible!

So far it has been difficult to reproduce so we can't easily track where the issue is - after you check the formatting again, do you make and edits? Or do you simply load the category edit page from the Articles & World Management and then click "View in World" to inspect if the formatting has remained the same in the Presentation page? There seems to be an override at some point of your process but I haven't located where or what's causing it.

It doesn't matter if I come in through the World View or the Management View. From the World View, it just shows the category name and no contents. From the Management View, it shows everything turned back on and in the default positions. I can do screenshots?

Since I don't appear to be able to upload images here, here's a link to a hosting site. It shows what a reverted category looks like both from the World view and the Management view.
https://postimg.cc/gallery/y91SyXm