Cannot purge "empty"? layer

[stekicarYWNUL]

I have tried to purge drawing after I moved all entities to new 5-TXT layer. After purge command all non-used layers were removed except one: LAYER_10. For some reason, it is connected to 5-TXT layer either through AcadBlockReference entities or something else. If I delete all entities from 5-TXT layer, LAYER_10 can be purged. Layer is not frozen nor locked. I checked with SelectionSet and no entities are located on this LAYER_10 layer. What am I missing? Drawing attached.

[Ed__Jobe · Accepted solution]

If you look at "LAYER_10" in the "Find non-purgable items" tab in the PURGE command, there are no links to other references. This makes me think that the layer was renamed from a non-purgable layer like DEFPOINTS.