The browser might not be able to send the request for fetching repositories or tags to the server.
There could be various reasons such as:
-Lack of network connectivity
-Firewall
-Ad blockers
-DNS errors
Please contact your network administrator or check your network configuration and connectivity. Try running az acr check-health -n yourRegistry
using your Azure CLI to check if your environment is able to connect to the Container Registry. In addition, you could also try an incognito or private session in your browser to avoid any stale browser cache or cookies.
Source : Azure Documentation Link