What version are you running?
2.5.2
What's the URL of the page containing the problem?
/admin/feed/news/
What steps will reproduce the problem?

Visiting ReviewBoard's admin interface on a slow internet connection
Server completely hangs at feed request

What is the expected output? What do you see instead?
Users should be able to proceed without loading the feed
What operating system are you using? What browser?
Windows 10, Chrome 50.0.2661
Please provide any additional information below.
The bug is related to djblets/feedview/views.py, a timeout should be set on urlopen request. Could be better if the feed can be loaded asynchronously.