Fretboard diagrams are not exported to MusicXML
Chord diagrams added in musescore are not exported to musicxml files.
Steps to reproduce:
1) Create new Musescore file.
2) Select instruments.
3) Add one acoustic guitar stave and one linked tab stave.
4) Using the advanced palette, add any chord diagram.
5) Export the file to musicxml.
6) No chord diagram is in the file (I tried visualizing the file using Soundslice's mxl viewer and manually inspecting the xml content).
Note : there is an old related issue (#95886) where it is said that diagrams with a chord symbol should be exported without problem. This is not the case here as I made sure that there was a chord symbol is linked to the diagram here.
Problem reproduced with