Custom Geocaching icons - icons for waypoints not recognized anymore

When using a custom Geocaching icons pack, then the icons for waypoints are not recognized anymore in 4.36.1 (see https://docs.locusmap.app/doku.php/manual:advanced:customization:icons#list_of_possible_icons):

• wpt_final.png
• wpt_parking.png
• wpt_question.png
• wpt_referencepoint.png
• wpt_stage.png
• wpt_trialhead.png

The zip file is correctly located in the Locus/icons directory, is unchanged and worked for many years in Locus 3 and 4.
Other icons still display correctly.

If you try to select the icon pack in expert settings, the pack is not available.

As soon as you add one additional icon with a different name to the pack, e.g. diff_10.png, the pack is available in expert settings again and the icon is also shown correctly on the map.
Same is true if you simply rename one of the icons to diff_10.png.

This started with one of the recent version updates, don't know exactly which one.

Would be nice if the waypoint icons are handled the same way as it was for many years.