Game output log cuts off messages and does not show scroll bar

The bug

The game output log cuts off messages if they are too long, but does not show a scroll bar either. Resizing the windows might not help because it first tries to fit additional columns, such as class and thread name.

Note: The behavior changed slightly, possibly due to the fix for MCL-12594. This now only occurs if the message does not contain whitespaces.

How to reproduce

1. In game, run the following command

   /say aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaEND
   

2. Check in the game output log whether you see "END"
   It is cut off and there is no way to scroll