UserAgent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.115 Safari/537.36

Example URL:
https://brytewave.com/

Steps to reproduce the problem:
1. Go to https://brytewave.com
2. Get an account
3. Get access to a textbook
4. Go to any page within the textbook.
5. Go to the next or previous page, either using the left or right arrow keys or by clicking the left or right arrow icons which appear on the page while hovering the 
6. Attempt to scroll up or down the page using the up or down arrow keys.

What is the expected behavior?
You can scroll up and down using the arrow keys.

What went wrong?
You cannot scroll up or down using the arrow keys until you use the mouse to click somewhere inside the page.  After that you'll be able to scroll up and down with the arrow keys until you go to the next or previous page.

Does it occur on multiple sites: No

Is it a problem with a plugin? No 

Did this work before? N/A 

Does this work in other browsers? No
 Firefox 54.0

Chrome version: 59.0.3071.115  Channel: stable
OS Version: Fedora 25
Flash Version: Shockwave Flash 26.0 r0

If you click inside the page (not on one of the arrow icons) you'll get this error in the console:

Error: Node [object HTMLDivElement] not found. Partial CFI found: https://jigsaw.vitalsource.com/assets/v1/jigsaw/puzzle_pieces/index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js

If, after clicking inside the page, you go to the next or previous page via using the arrow keys, you'll then get this error message in the console:

Uncaught TypeError: Cannot read property 'words' of undefined
    at Object.contentReady (index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:6)
    at Object.callBookTypeContentReady (index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:7)
    at Object.initNextPage (index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:7)
    at Object.<anonymous> (index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:9)
    at i (index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:4)
contentReady @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:6
callBookTypeContentReady @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:7
initNextPage @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:7
(anonymous) @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:9
i @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:4
13:09:33.842 index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:3 XHR finished loading: POST "https://jigsaw.vitalsource.com/api/v0/books/9781457649905/logs".
send @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:3
ajax @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:3
a.flush @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:9
(anonymous) @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:9
fire @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:4
(anonymous) @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:6
(anonymous) @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:9
i @ index-6db1d21de39e903ec0a6fd1befbffd80eed844ecda9f03b7d94a3e49aac30acd.js:4