Original render:

(test_transposing_accidentals_1383.musicxml)

Transposing 1 halftone up:

osmd.Sheet.Transpose = 1;
osmd.updateGraphic();
osmd.render()

Transposing back down to original key (should be same as original render):

Before:

After the fix:

osmd.Sheet.Transpose = 0;
osmd.updateGraphic();
osmd.render()

This fixes the unfinished part of #1383.