I click on a webp image, and this add-on doesn't find it?!?

Add-on did absolutely nothing.

(UPDATE 12/02/19: I have found the perfect Addon/Extension for this kind of Job, it is the "Bulk Image Downloader"! It downloads for me only the specific images I ask from the certain Link. And also the REAL full size images. Not the thumnail sizes... So I am going to use that one instead). If in the future add these great features the BID has to this extension as well, I probably download this as well.
-------------------------------------------------------------Old review: This is a great Addon, with great potential to evolve. But I gave 3 stars because it shows me smaller sizes of the images I wanted to download from a certain tab. The actual original images sizes are 1068x1600 pixels (when I right click and open them in a New Tab), but your Addon extension is downloading for me smaller sizes of 467x700 pixels. It reduces the sizes and the quality of the images. That's why I gave only 3 stars. This is very important for me the quality and pixels. Is there any option to choose to fix that? Thanks? If there is I will rewrite me review and give 5 stars.

it's really awesome thanks for the extension

Finds all of the images and filters them correctly, but when downloading the resulting zip contains only one of the selected images. So currently not really an improvement on manual download, but looks like a good start.

Perfect. Well done! Thank you

Well, works with most sites where image somehow could be tracked.
Doesn't work with Flickr & Tumblr for example tho.