Update to 5.0.2 with German informell / Österreichisches Deutsch configured causes "Oops!....Error"

Description:

Using the language "Deutsch informell" or "Österreichisches Deutsch" (with RocketChat 5.0.2) causes a "Fehler Oops! Something went wrong. Please reload the page or contact an administrator."
Reloading or delete the local browser cache changes nothing.
Every chat or room now throws this error message on the client side.
The only workaround is to use the default language (English).

Steps to reproduce:

1. Select "My Account"
2. Select "Preferences"
3. Change "Language to "German informell" or "österreichisches deutsch"
4. Back the Chat interface, and the "Oops! Error appears.5.

Server Setup Information:

• Version of Rocket.Chat Server:
• Operating System: Ubuntu 20.04
• Deployment Method: from source
• Number of Running Instances: 1
• ReplicaSet OpLog: Enabled
• NodeJS Version: 14.19.3
• MongoDB Version: 5.0.10

Client Setup Information

• Desktop App or Browser Version: Chrome (104.0.5112.79) ,Firefox ESR ,Edge
• Operating System: Windows 10 LTSC / MacOS 12.3.1

No source file, test, or entry point is named. First reproduce the client-side error after selecting either German language option, then trace the failing chat or room view and its locale data. Done means both German variants work without the Oops error while English remains unaffected.