If I wanted this to be a proper extension, I'd have to pay Google $5. I don't really want to do that, so if you're okay with a bit of "hacking", then the following steps will install the extension on your Chrome (or Chromium based) browser.
At the top of this page, you should find a green button Code, on the right side of the page:
If you don't see that, look for the <> Code tab under the page header and open that in a new tab or window. The green button will be on that page instead.
From the popup that appears, select Download ZIP at the bottom:
Find the downloaded ZIP file and extract the files to a folder. This folder can be anywhere on your PC, as long as it's extracted, and not left in its ZIP format.
In the top right corner of Chrome, you'll find three vertical dots. Click that and find Extensions and then Manage Extensions:
This opens the chrome://extensions/ page.
In the top right of that page, you will see a toggle Developer Mode:
This will show you some special buttons in the top left.
The Load unpacked is the button we need - click that, and navigate to the folder you extracted the ZIP to. You don't need to select a file (Chrome will find the files it needs).
Once done you should see this somewhere on the page (or something similar):
Navigate to any of the supported websites:
You'll see the page go blank for a second while the scripts remove all the thumbnails, then it will come back and everything will be hidden.
If you find something isn't being removed / if you have any questions / if you want another site to be blocked:
Contact me over on my website: https://www.philipbkemp.net/contact