fix constrained drag
fixes for TimeSig
fix merge problem
cleanup: duplicate line, unused header
fix #15721: Pasting selection including a line causes crash
fix import of drumset in some GP files
better detection of drum staff in GP import
fix #21326: [MusicXML] import of page format is not working
Custom page size was marked as A4
fix #19163: Elements selected in 1.2 score don't de-select