On startup LibreOffice opens a page full of BASIC macros. In [My Macros & Dialogs].AncientGreek->Registry. The code that seems to be causing the problem is: If IsMissing(isPath) then If not isPath then <-- this line is highlighted GetMyRegistryValue = sRegVal Exit Function End If End If I acknoledge the error, close the window and everything appears to be working correctly, but I am not editing Greek at the moment. (FWIW Hebrew appears fine.) I noticed that the initial file selection menu doesn't open until after the macros windows is closed.
https://extensions.libreoffice.org/en/extensions/show/ancientgreek Release "1.6b9-no-doc" is described "... Fixing the "Argument is not optional" error message for all Message Boxes on LibreOffice 7.4". This was just a bug in the extension; it was fixed. Update your extension. Closing NOTOURBUG.