Product and version: FMP15 and WebDirect on FMS14 and 15
OS and version: OS X 10.11.5
Browser and version: Safari .1.1 (11601.6.17) and Chrome Version 51.0.2704.103 (64-bit)
Hardware: iMac 27
Description: Odd horizontal sliding of popover when app or browser window is sized narrower and horizontal scrolling is used.
How to replicate: Add popover to layout, narrow window to less than 100% layout width, scroll horizontally left and right.