MusicXML export: left-hand side repeat sign is included in the previous measure width
The exported MusicXML measure width includes the width of the repeat sign in the left-hand side of the next measure. I believe it is not the intention of the MusicXML format, and for example Finale behaves differently.
Looking at the code, the export simply asks for the bbox of the Measure instance. I guess the bounding box includes the complete following barline, instead of its left half.
The issue is also present in the latest nightly build.