Clef on first note of system becomes header clef after save and reload
Ubuntu 14.04, GIT commit: e255575
Reported in http://musescore.org/en/node/46021
1) My First Score, or new from Treble template, key of Bb, 4/4
2) add a single quarter note to measure 5 (first measure of system 2)
3) click note in measure 5
4) double click bass clef icon in palette
Result: clef is added as a mid-measure clef change. The initial treble clef is left intact, and no courtesy clef appears at end of previous system.
There is code to detect an attempt to add a clef change on the first chordrest of a measure, and to convert it from mid-measure to "regular" if so. But this apparently doesn't work at the beginning of the system if there is a key signature there.