Files not opening

Very odd.

I use an app called Bean [3.2.9] for text entry, nicer than TextEdit, simpler than Pages , but all of a sudden in 10.14.3 [about to update] it won't open its own files.

When I double-click on a file's icon it brings the app to the front and if there is a doc already open it brings that to the front too. The new file is there under the Window menu, but can't be seen at all. A quit is not a fix, a restart is, opening any file that was open before and the first new one I try, but no more after that. The files, always rtf, do open in TextEdit.

Any ideas?

Colin