New app launcher icons

Added new application icons.

Hint about updating the application icon

When approaching the holidays, a hint will appear asking you to set a themed application icon for this holiday. When you click on a hint, the icon changes.

Instantly change the application icon

Now, when you change the application launch icon, the application will not restart (as it works now in the official client). The application icon will change instantly. The only exception is the very first update of the icon, and all subsequent ones are updated immediately.