How to reproduce:

• You need a smartcard with expired certificates (e.g. an old NetKey v3 card)
• Insert the card and open the smartcard window
• Delete the certificates belonging to the first two card slots
• Close the smartcard window and open it again
• Kleopatra will load the card certificates and show a progress bar. It's hard to separate the progress overlay from the red certificates shown in the background.

This is also mostly a cosmetic issue and only occurs if some certificates are loaded from the card while other expired certificates are already available. -> Low priority