Setting an earmark with Ctrl means you can't enter a non-earmark value
I just upgraded to Ubuntu 19.10, and the earmarking seems semi-broken. If I type a number in a cell that has not been earmarked, it enters that number in the cell. If I enter one or more earmarks, using Ctrl+digit, then typing a number in the cell without Ctrl, will only set/clear the earmark.
Entering the earmarks using right-click does not cause this problem, and clearing all the earmarks using right click fixes the problem for that cell.