File Upload not visible when chat editor is in full-screen mode

Reproduction Instructions

  1. Load Phabricator in IE11
  2. Go To A Chat
  3. Enter chat textarea
  4. Open full screen mode
  5. Open the file upload dialog

Problem:
The overlay from the upload is always behind the full screen mode window and not usable.

The z-index of .jx-client-dialog is current on 14;

The z-index of .remarkup-control-fullscreen-mode is current on 50;

Phabricator/Arcanist Version
latest

Fix:

.remarkup-control-fullscreen-mode {
  z-index: 50;
}

.jx-client-dialog {
  z-index: 51;
}

.jx-tooltip-container {
  z-index: 52;
}