I’ve been collecting images for almost 20 years.
Sites and software come and go. I use to try to use delicious for bookmarks, but sometimes the bookmarklets don’t work and I get the feeling Yahoo isn’t really supporting it so it’s only a matter of time before it stops working I think. (it’s done now? @ralph? ) Not to mention it doesn’t work to save posts from IG, FB, etc…
Your best bet is to download the image and organize local storage of it for reference. I download images or screen captures and file them into folders. I don’t bother with tagging or to fine filing, but have folders for packaging, graphics, photography, product, footwear by category…
…So far I have about 8Gb of images / a little over 22,000 images… mostly shoes however 
R