What version are you running?
3.0
What's the URL of the page containing the problem?
http://biedronka.emea.nsn-net.net/dashboard/
What steps will reproduce the problem?

open some submitted review
switch from "Reviews" tab to "Diff"
"Download Diff" button disappears


What is the expected output? What do you see instead?
"Download Diff" button visible all the time
What operating system are you using? What browser?
Chromium Version 62.0.3202.94 (Official Build) Built on Ubuntu , running on Ubuntu 17.10 (64-bit)
Please provide any additional information below.