Unable to load any skillmap activity in prod

[eanders-ms]

When I try to start a skillmap activity, I see a double header and the editor fails to load.

Repro steps:

1. Go to https://arcade.makecode.com.
2. I was not signed in. You may want to ensure you're signed out to get the same repro.
3. Click "Beginner Skillmap". This will open https://arcade.makecode.com/--skillmap#beginner in a new tab.
4. In the skillmap, select an activity to start. I chose "Greeting Card".
5. Click the "Start" button to start the activity.
6. Notice that the editor fails to load, and the double header:

System:

• Windows 11
• Chrome 104

[eanders-ms]

Looks like it's inconsistent. It will load about half the time for me.