STEPS:
1. Goto was.sandbox.google.com/mail/mu/?sky=test
2. Log in with any account
3. Open compose->select attachment icon

EXPECTED RESULTS: Attachment opens popup should come

ACTUAL RESULTS: Screen goes dim and later no response for any action, need to refresh the page






App Version: 56.0.2904.0
iOS Version: iOS10.2 beta 2
Device: iPhone 6s Plus
URL: gmail.com

Steps to reproduce:
  1. Open gmail.com and log in
  2. Start composing a new email, filling in subject and body
  3. Close the draft

Observed results:
A menu should slide up from the bottom asking if you want to save or discard your draft.

Note: Sometimes issue is not reproducible when 'To' field is filled 1st. 

You can also repro this same issue sometimes with instead of closing the email draft trying to attach a photo instead - the screen dims but the menu doesn't slide up from the bottom.

Expected results:
The screen dims with the overlay, but the menu doesn't appear.


Number of times you were able to reproduce: 5/5
Bug reproducible after clean install: Yes
Bug reproducible after clearing cache and cookies: Yes
Observed behavior in Chrome Mobile on Android: n/a
Check for similar behavior on Firefox/Safari: Safari: No, Firefox: No
Bug reproducible on current stable build (App Version, iOS Version): No
Bug reproducible on the current beta channel (dogfoody) build (App Version, iOS Version): Yes on 55

Shared video at: https://drive.google.com/open?id=0B5SCqattaLcqaklqNFRoQU12ckk