There doesn't exist a native way of doing that on the network. However, as already mentioned in Schrödinger's cat's answer, you can use the image search option with Google, targeting this site via
Note though that this may only be valuable in select instances where posters did use images. Some threads only post an image in the ...
I experience more or less the same:
No matter what file I upload, the image https://i.stack.imgur.com/gGfsT.png is displayed:
I helped myself as follows:
I browsed to the page https://imgur.com/upload and uploaded my image-file there.
The file got uploaded and the uploaded image was displayed.
I clicked the image with the right mouse-button.