Downloading From jwplayer
When trying to download from a site that uses jwplayer, sometimes youtube-dl fails and it may be necessary to find and download a video from a link manually.
Looking in Inspect Element
Looking in Inspect Element seems very trivial, and sometimes even childish, but it can actually be a useful resource in figuring out where things are.
Using Firefox or one of its derivatives
Firefox has a very handy Network tab which allows you to view exactly what kind of HTTP requests the browser is sending. This is pretty handy when you're trying to understand what scripts and style sheets are being used.
The rest is pretty simple. All you need to do is play the video and Firefox will show you exactly where the video source is coming from. Look for a HTTP 206 Status (Partial Content) and one of those will have the link to the source (right click and select Copy URL).
Using virtually anything else
Usually, jwplayer is set as its own entity so you won't be able to right click on the player directly to open Inspect Element. You'll need to open Inspect Element somewhere nearby and open enough tabs to find some javascript code. The code should be between:
<script type="text/javascript">..</script>
The raw URL values are typically stored as base64 values such as:
d2lraS5iaWJhbm9uLm9yZw==
It's simple to convert that using an online base64 decoder such as https://www.base64decode.org/
There should be several links, just use the tool several times to find the one you want or if you can read javascript, you could also use a javascript beautifier to figure out how the links are stored.