Notes get erroneously erased and chords replaced with MIDI keyboard entry

Using a fresh install of Musescore 3.0.0, starting with a blank sheet.
If I enter notes: C, D, E, E, D, C with the Qwerty keyboard, I get: C, D, E, E, D, C on the sheet, as expected.
If I do the same with a MIDI keyboard, I get: C, D, rest, E, D, C. The third note gets deleted when I enter the 4th note. It looks like a regression. Musescore 2.3 did not do that. The bug makes it inconvenient to enter melodies through a MIDI keyboard.
There is another issue with MIDI keyboard entry that may be related, although I cannot tell if it's a bug or a feature. If you want to enter two consecutive chords that have a note in common, you have to be careful NOT to press the common note first. If you press it down first, the new chord replaces the first, instead of following it. For example, to get C+E followed by E+G, you need to: press C and E down, then up, then press G down then E down, then up. If you press E before G, the first chord is lost and overwritten. That behavior makes typing piano music with a MIDI keyboard quite difficult.
FYI my keyboard is an Alesys VX49 (on USB port). I haven't tried with another model, but I don't think it matters.