This is still not quite fixed
On Sheet1 I have a named range 'Test' which refers to A1. The value in A1 is 1. On Sheet2 I have a cell which refers to 'Test' (ie. B5 value is "=Test"). Updating the A1 on Sheet1 programmatically while Sheet2 is active causes the visual bug.
Switching tabs fixes it, but is slow. Is there a way to force a refresh as a workaround for now?