Inability to create new text lines in frames

Current 3.0 dev. d637874 / Windows10

1) "Untitled" score
2) In a frame, eg the default vertical frame: add some text
3) Press "Entry" key to move down to a next line

First result: the cursor moves as expected

4) Continue to enter text in this created new line

Result: the cursor returns to the first line, and so on each time