Got this from support. I am trying in a second App Hosting backend first, though:
After an investigation I can see that this is a known issue already reported with the engineering team, at this time the workaround is to publish the application manually using App Hosting, since the engineering team is working on a quick fix for this, I’ll report that you are facing this issue.
In the meantime could you please try this workaround:
Open a new terminal, you can go to the left up (on coding view) where there is an icon with 3 little lines → Terminal→New terminal, that will give you access to the workspace’s terminal where you will be able to run commands, then execute the following commands:
1. firebase init apphosting
2. npm run build
3. firebase deploy --only apphosting
Keep in mind that you will need to replace the existing apphosting.yaml file. After replacing the file, you will be prompted with a question asking you to “Specify your app’s root directory relative to your firebase.json directory (/)”. Simply press Enter to accept the default root director
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