• Electron version: 1.7.0
• Operating system: macOS

Expected behavior

Electron works with --debug or -debug argument

Actual behavior

Electron won't run with arguments above.

How to reproduce

I've tried the standalone .app and the npm modules:

• for standalone .app it shows an error and returns a non-zero
  (with "IOVARendererID property not found" the welcome window appears and I've manually close it)
  

• for npm module it just won't start and no error returns
  

I can confirm the --debug works with previous versions including 1.6.9 beta