Note-Input bar collapses back to single-line early when window isn't wide enough

The Note-Input bar is normally displayed on a single-line, and when the window isn't wide enough to display everything, that line has a >> for show-more. This expands the rest of the Note-Input functionality, shown on multiple lines.

This expanded Note-Input bar collapses too early, often before I can click on the Note-Input feature I want.

For example, I make the window small enough that the 'flat' option is hidden, so >> for show-more expands the Note-Input bar. I move my mouse towards 'flat', and the Note-Input bar very often collapses to a single line before I get there, hiding the 'flat' option again even if I'm careful to keep my mouse within the now-multi-line bar.

Steps:
1. Open MuseScore
2. Shrink the window size until the Note-Input bar's 'flat' option is hidden behind >> show-more.
3. Click on >> to expand the Note-Input bar.
4. Move the mouse toward the 'flat' option, trying to click it without the Note-Input bar collapsing.

A video of this example is at this vimeo link: https://vimeo.com/382650124

Current behavior: The Note-Input bar seems to collapse early if I move my mouse over one of the buttons in-between in the expanded area not the original area.

What I expected: The Note-Input bar should only collapse back only when the mouse leaves the exanded area.