Your system information

• Steam client version (build number or date):
  
• Distribution (e.g. Ubuntu): Xubuntu
• Opted into Steam client beta?: [Yes]
• Have you checked for system updates?: [Yes]

Please describe your issue in as much detail as possible:

The "Launch game as soon as it's ready" option label string isn't populated correctly. Instead the user sees "#SteamUI_JoinDialog_LaunchGameReady" in its place.

Steps for reproducing this issue:

1. Buy a game
2. Install that game
3. While the game is installing, download some free DLC for that game
4. Notice the option's label text is not replaced with the proper string