I'm using QGIS 3.18.0 on Windows 10 (from OSGeo4W Network Installer).
I have a polygon-shapefile with an attribute table including the attributes "signatur", "r", "g" and "b":
I'm using Simple Fill together with Centriod Fill with Font Marker to distinguish between the polygons:
I'm using Data defined override to set the color of the Font marker to be based on the values in the "r", "g" and "b" fields:
I'm using Data defined override to set the Font Marker character(s) to be based on letters in the "signatur" field:
Looks like this in the QGIS canvas:
Looks the same in the Layout. In the Item Properties - Legend Item Properties - Symbol settings has the same setup as in Layer Styling. However the Legend patch is either missing the actual Font Marker character (if I have chosen a blank character) or showing an "A" (A seems to be the default selected character) in the default color red:
I want the patches in the legend to show the same Font Marker (characters = "signatur"-value) as in the map, and not like this:
Is that possible?