SyntaxError: "[Object Object]" is not valid JSON when parsing event.data

[CorgiTT]

Description When handling a message event, the following error occurs: SyntaxError: "[Object Object]" is not valid JSON

This happens at the line: const parsed = SuperJSON.parse(event.data);

Details

• File: index.js
• Line: 5924
• Stack: Vue DevTools, Vite, SuperJSON From the debug panel, event.data is sometimes an object, not a JSON string. When SuperJSON.parse is called on an object, it throws the above error.

Example of problematic data:

event.data = {
  payload: '{"json":{"event":{"event":"shutdown"}}}',
  source: "proxy->server"
}

Steps to Reproduce

1. Trigger a message event where event.data is an object instead of a JSON string.
2. The code tries to parse event.data using SuperJSON.parse.
3. The error is thrown: "[Object Object]" is not valid JSON.

Expected Behavior The code should check if event.data is a string before parsing, or handle objects appropriately.

Environment

• OS: macOS m3
• Browser: 137.0.7151.120 (arm64)
• Project: Vue DevTools + Vite