App issue locally after yarn dev command about amazon-chime-sdk-classroom-demo HOT 2 CLOSED

In my macOS Catlina, I just removed node_modules folder, deployed the app (Step 1 in Option 2), and then ran yarn dev. I could execute the dev app without the Error: Exited with code 9 error.

Versions:
macOS - Catalina V10.15.6 (19G2021)
Node - v12.16.3
NPM - 6.14.4

This classroom demo is using the electron-react-boilerplate project. In the following open issue, some users are having the same Exited with code 9 error, but the cause is unknown.
electron-react-boilerplate/electron-react-boilerplate#2535

yarn dev worked in a similar setup. Could you try deploying and running yarn dev in Node v12.16.3 and NPM 6.14.4?

from amazon-chime-sdk-classroom-demo.

2. Audio/Video not working locally (it works in application under release folder):
   I'm was able to join as a Teacher/Student in app. & web socket seems to be work. Issue is with audio/video, unable to access them locally in app.

Have you allowed the microphone and camera permission before? When you open the dev app for the first time, the permission dialog would pop up.

You can also enable the permission in the macOS "Security & Privacy" settings. Make sure that "Terminal" and your app name in the release folder are in the list.

"Terminal" is for the local demo app launched with yarn dev. I confirmed that audio calling didn't work when I disabled the Terminal checkbox. We'll add it to the doc.

from amazon-chime-sdk-classroom-demo.