Hi,
B4A 10.2, OpenJDK, Windows 10 Pro French, when opening a sample project (the one related to the B4XPages, three pages and a canvas where we draw random colors), I got the error : the given key was not present in the dictionary. Attached a screenshot.
I was not doing anything, just opening the project.
Yes, I was able to run the project and nothing noticeable at all. I am even not able to reproduce it (I've downloaded the sample project again and opened it without any warning). I will enable the IDE logs as you suggested.