I'm not sure if this is because of Firefox's cache, or e-h DL'er but when you click an image and then back to the original page, an additional EH download field is added to the same page.
It's probably an issue on Firefox when it caches the previous page. #251 said it happens on Firefox with GreaseMonkey, by switching to Tampermonkey the issue is resolved.
I'm not sure if this is because of Firefox's cache, or e-h DL'er but when you click an image and then back to the original page, an additional EH download field is added to the same page.