Merge pull request #7353 from electron/no-login-item-apis-on-mas

document lack of MAS support for login item APIs

diff --cc docs/api/app.md
index 21dca1d,8f73d64..745b0c4
--- 1/docs/api/app.md
--- 2/docs/api/app.md
+++ b/docs/api/app.md
@@@ -835,9 -838,12 +838,12 @@@ Returns `Object`
  
  Set the app's login item settings.
  
+ **Note:** This API has no effect on
+ [MAS builds](docs/tutorial/mac-app-store-submission-guide.md).
+ 
  ### `app.isAccessibilitySupportEnabled()` _macOS_ _Windows_
  
 -Returns a `Boolean`, `true` if Chrome's accessibility support is enabled,
 +Returns `Boolean` - `true` if Chrome's accessibility support is enabled,
  `false` otherwise. This API will return `true` if the use of assistive
  technologies, such as screen readers, has been detected. See
  https://www.chromium.org/developers/design-documents/accessibility for more