Not sure if this is already in prod/canary. But it's in current master.
Repro:
- Run local server
- navigate to everything.amp.max.html example
- Locate the Open Lightbox button
- Click it
- Click close dialog
- Notice a visible black border appearing.
Computed styles for body changes as follow:
/* Before Opening Dialog */
border-top-color: rgba(0, 0, 0, 0);
border-top-style: solid;
border-top-width: 0px;
height: 628px;
width: 414px;
/* After Opening Dialog */
border-bottom-style: none;
border-left-style: none;
border-right-style: none;
border-top-color: rgba(0, 0, 0, 0);
border-top-style: none;
border-top-width: 0px;
height: 628px;
width: 414px;
/* After closing dialog */
border-bottom-style: solid;
border-left-style: solid;
border-right-style: solid;
border-top-color: rgba(0, 0, 0, 0);
border-top-style: solid;
border-top-width: 0px;

Seen on iOS 9.2
Not sure if this is already in prod/canary. But it's in current master.
Repro:
Computed styles for body changes as follow:
Seen on iOS 9.2