Note entry in expanded measures
Latest/current release of MuseScore 3; Windows 10 latest feature release; probably true for others.
By "expanded" I mean a measure whose properties have been edited to have more beats than the time signature indicates, for example, 6 beats in 4/4 time, which I will use as an example here.
The problem does not occur in the last measure of the piece. To reproduce, create a new, empty piece of two measures in 4/4 time and edit the properties of both measures to have 6 beats each. (This will allow to observe that the problem occurs in the first but not the last measure.)
Select the entire first measure, not just the first rest in the measure. Press "N" to begin note entry. Observe that it begins at the second rest of the measure, not the first as it should. Press "N" again to end note entry.
Select the entire last measure. Press "N" to begin note entry. Observe that it begins at the first rest of the measure, as it should. Press "N" again to end note entry.
It will not be possible to observe the problem in a one-measure piece. It will be possible to observe the problem in any measure but the last of a piece with two or more measures.