Does what you expect it to do. I have three complaints though.
1: The CPU usage is absolutely absurd. Unless you have a strong PC, you should probably not use this add-on. It seems like it gets worse the more sites you whitelist. I've had to re-install it multiple times to reset it (and I have an AMD 7 3800x).
2: Would be nice to have a blacklist, but as an alternative, you can block elements (or images) manually with an adblocker.
3: Some reCAPTCHAS or websites using Cloudflare simply won't load with this extension. You can't even whitelist them and re-load the website. You have to disable the extension and open the site in a new window to fix it.

I second the opinion that a blacklist would be a welcome addition to this addon!