On itself you could ponder on why you need this...
Apart from being insatiable curious that is...

But if you want to block ad servers for example?
Did you ever notice they got these very cryptic, non-descriptive names?
PITA right?

Well, uBO-Scope can helps loads there I noticed when I tried it. So you can identify what that URL is (e.g. postrelease.com, hummm, well, look in uBO-Scope, and find it's an ad server).
So with that info, you can set-it-and-forget-it in uBO or uM.
Cheers Gorhill!

uBO, uMatrix and uBO-Scope are very useful for network protection extensions.

Very useful extension for privacy-focused users.
It's important to read the full description to understand how it works.
Thank you!

This add-on builds over time a local database of 1st party/3rd party occurrences. It is a very interesting attempt at personalizing the benchmarking of ad-blocking/privacy-enhancing add-ons.

The concept seems similar to Privacy Badger, in the sense that the add-on experience is personalized to the user. The core difference is that the add-on does not block anything, it just aggregates stats based on your browsing history.

Right now, I am using uBlock Origin to block ads ("very easy mode") and Privacy Badger to enhance my privacy. I was really surprised that, despite using Privacy Badger for weeks, uBO-Scope would tell me that google-analytics was still not blocked! I am going to switch back from Privacy Badger to uBlock Origin with EasyPrivacy subscription now...

Regarding Privacy Badger: Google Analytics is considered first-party and not blocked by Privacy Badger. When I posted a negative review about it on the addon page, this review was deleted for a spurious reason. When I posted a new review, it was again deleted without even notifying me by email, like it did for the first review deletion. So I am stating it here, as I learnt about it thanks to uBO-Scope: The heuristic of Privacy Badger is unable to block Google Analytics. This is documented in several closed Github issues:
https://github.com/EFForg/privacybadger/issues/340
https://github.com/EFForg/privacybadger/issues/367

Essential upgrade to uBlock Origin.

Not sure if I use it correctly, but if I do, there should be a small "training period" to gather initial data. On first use it actually shows me 400 points for AMO so I was expected to see NSA backdoors instead of Google Analytics.

Still, this addon provides one of the most smart and reasonable way to determine unwanted 3rd-party services.