Antigravity on macOS completes Google OAuth in browser, but app never signs in. Browser callback reaches localhost successfully, then main process crashes

Google Antigravity
1

Antigravity on macOS completes Google OAuth in browser, but app never signs in.
Browser callback reaches localhost successfully, then main process crashes.

Version: 1.20.6
Bundle ID: com.google.antigravity

Relevant logs:

  • auth.log shows localhost OAuth server starts and stops normally
  • main.log crashes exactly when OAuth server stops:
    TypeError: Do not know how to serialize a BigInt
  • extension log then shows:
    Failed to get OAuth token
    state syncing error: key not found

Repro observed on:
2026-03-20 23:48:07
2026-03-21 00:06:22

2

Yeah, seems exactly like the thing i’ve been telling everyong for a week now.

You have multiple Google accounts on your default system browser and possibly multiple Google accounts in your macs Settings > Accounts.

Set it to one google account in your mac settings / accounts, and set your default system browser to one google account and set your antigravity to one google account. all have to be the same matching account.

i detail the whole thing
https://discuss.ai.google.dev/t/possible-global-quota-refresh-reboot-restart-antigravity-and-check-looping-7-day-lockouts-over