Unable to add mid-measure clef on the first tick of a measure
MuseScore has supported mid-measure clefs on the first tick of a measure for a while, but in the master branch, the ability to create them has been lost. When dropping a clef onto the first ChordRest in a measure, the clef is supposed to be inserted right before the ChordRest, in the same measure. Instead, it is moved to the end of the previous measure.
I suspect that this a result of commit 9f12f2aa7c to fix #139316: Regression: inability to change a clef inside a system leads to crash. Werner has confirmed that it is indeed a bug.