UserAgent: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36

Steps to reproduce the problem:
1. Open fiddle https://jsfiddle.net/6hvkghdc/
2. Type a 3 characters in the text area each on a separate line
3. With the cursor on the last line, press [Page Up]
The entire page scrolls up hiding the top part of the page/messing up the layout. the only workaround seems to be by resizing the browser window 

What is the expected behavior?
Web page should not scroll. Page's layout should not be affected when pressing Page Up/down buttons inside a textarea

What went wrong?
The entire page scrolls up hiding the top part of the page/messing up the layout. the only workaround seems to be by resizing the browser window

Did this work before? N/A 

Does this work in other browsers? N/A

Chrome version: 59.0.3071.115  Channel: n/a
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version:
 

Deleted: page-layout_before.png 55.9 KB

	page-layout_before.png 55.9 KB View Download

Deleted: page-layout_after_pressing_PageUp.png 47.6 KB

	page-layout_after_pressing_PageUp.png 47.6 KB View Download