Meta issue: Security improvement

Checklist:

• Remove SameSite=Lax -> SameSite=None cookies patching (fixed in: https://github.com/nextcloud/talk-desktop/pull/22)
• #18
• Follow Electron / Best Practices / Security
  • 1. Only load secure content
  • 2. Do not enable Node.js integration for remote content
  • 3. Enable Context Isolation
  • 4. Enable process sandboxing
  • 5. Handle session permission requests from remote content
  • 6. Do not disable webSecurity (https://github.com/nextcloud/talk-desktop/pull/22)
  • 7. Define a Content Security Policy
  • 8. Do not enable allowRunningInsecureContent
  • 9. Do not enable experimental features
  • 10. Do not use enableBlinkFeatures
  • 11. Do not use allowpopups for WebViews
  • 12. Verify WebView options before creation
  • 13. Disable or limit navigation
  • 14. Disable or limit creation of new windows
  • 15. Do not use shell.openExternal with untrusted content
  • 16. Use a current version of Electron
  • 17. Validate the sender of all IPC messages
  • 18. Avoid usage of the file:// protocol and prefer usage of custom protocols (https://github.com/nextcloud/talk-desktop/pull/1204)
  • 19. Check which fuses you can change
  • 20. Do not expose Electron APIs to untrusted web content