Notifications are broken after upgrading to 1.13

Reproduction steps:

• Install CR 1.12 and create multiple CR
• Check the dashboard to see the different events
• Upgrade to 1.13
• Open the dashboard

Expected result:

• Notifications are still displayed

Obtained result:

• An error is displayed: "Error while rendering notification Cause: [Null keys are not supported!]. Click on this message for details."