When moving to a dropdown item in a database grid and pressing ALT+Cursor Down there should be a list of items to select. In Libre Office 6.5 this still worked. Now the only way to open the dropdown list is to click with the mouse on it.
Could confirm the buggy behavior with LO 7.0.0.2 on OpenSUSE 15.1 64bit rpm Linux. Opening the Listbox with Alt + Down works well in LO 6.4.6.1. So this is a regression.
Not sure what the databse grid is exactly, I checked this bug in the Table Design window, with Field Type column. This started with the same commit as bug 135641. Marking as duplicate. https://cgit.freedesktop.org/libreoffice/core/commit/?id=8477bbf8d6867e656b8132f0ddd682d08590a547 author Caolán McNamara <caolanm@redhat.com> 2020-05-13 16:57:07 +0100 committer Caolán McNamara <caolanm@redhat.com> 2020-05-21 09:53:46 +0200 weld ListBoxControl *** This bug has been marked as a duplicate of bug 135641 ***