This is a minor cosmetic bug;
When you use a function that opens a window for additional input, like Pack or Unpack, the underlines that indicate the keyboard shortcut to toggle/activate that function don't show up until you actually enter something with the keyboard. This can be something as simple as just moving the cursor with the arrow keys, or pressing the Alt key.
See here;
Image: http://i45.tinypic.com/r1lzwx.png
This is strictly a cosmetic bug and doesn't cause any problems. It's just distracting to see something change out of the corner of your eye and not quite be sure what it was. It took me a while to realize that it was happening.
This happens on most windows such as Pack, Unpack, Split, Combine, etc, with the notable exception of the Multi-Rename window.
Pack shortcuts don't show underlines until you type
Moderators: Hacker, petermad, Stefan2, white
It is not a TC bug, it is your dumb Windows setting to hide shortcut keys until you press Alt. It is one of the first things I disable when reinstall Windows. 
It is enabled by default since Windows XP (maybe even 2K, not sure). Different Windows versions have this in different places, so please tell us which Windows do you use.

It is enabled by default since Windows XP (maybe even 2K, not sure). Different Windows versions have this in different places, so please tell us which Windows do you use.
After I posted, I started to wonder if maybe it was a Windows XP setting. After a little searching, I found that it's hidden in the Desktop properties under Appearance/Effects.MVV wrote:It is not a TC bug, it is your dumb Windows setting to hide shortcut keys until you press Alt. It is one of the first things I disable when reinstall Windows.
Thanks, I thought I knew all the stupid MS settings that needed to be turned off.