Application Version (from "Chrome Settings > About Chrome"): 53.0.2785.135
Android Build Number (from "Android Settings > About Phone/Tablet"): NMF19
Device: sailfish

Steps to reproduce: 
1) Visit http://tinyurl.com/fwd2016
2) Enable "Request desktop site"
3) Tap on the first pdf file.
4) Try to scroll down.

Observed behavior: 
The downward scroll attempt causes the page to scroll up as the URL bar disappears, and then starts scrolling down. Ending the scroll causes the page to pop to a different location.  Similarly, attempting to scroll up causes the page to scroll down as the URL bar reappears.

Expected behavior: 
Attempt to scroll downward should scroll downward.  Attempt to scroll upward should scroll upward.

Frequency: 
100% repeatable