Default positioning of hairpins.
This refers to Musescore 3.0.1 running in MacOS Mojave version 10.14.2.
The default position for hairpins and dynamics is below the stave, but in choral music it is common to put these marks above the stave. The default position of 'above' works fine for dynamics, but not for hairpins. If you put in all the hairpins (cresc, and dim.) with the default set to 'below' and then change it to 'above', they all move above, but is you set the default to 'above' first and then enter them, they usually still go below - but not always, which is odd!