I have a multi level dashboard coming along slowly:
When I click full screen however it doesn’t show me any more rows (there are lots), ie deosn’t expand to use all the real estate:
I’ve experimented with “auto fill container” but that just makes it huge at the start and seems to hide the full screen button.
What makes it worse is that i showed this behaviour to someone yesterday, and it didn’t do it , ie it did use all the real estate. 
UPDATE the middle panel, which has only 1 data row, DOES behave as it should and use all the space:
???