This works 99 % of the time and is one of my most used addons when collecting data. Thank you very much for your work. If I may suggest a few things I really would like;
1 - Options.. I always feel uneasy when there is no settings or anything to adjust if needed. Most of the time I could have had great use of some filters to only list the largest file, or only files that and also would be great with "select" options so I could easy and fast select the files I was interested in and click download.
2 - Option to change filetypes, preview size, and also window/font size. The buttons to click for download or open is very small and often missclicked.
3 - Custom filters for custom sites, that can be saved for later use.
4 - Almost forgot about this one.. but a way to re-order the listings so the files (images/pixels) are from sorted from big to small or small to big and if possible first/last found.

Would love to help you improve this addon, but I need to learn how to make addons first as I have really no clue. I do know php, mysql, css etc so if there is anything I could help with, let me know :)

Also, for the next update.. can you please add some ID on the divs and such so its easier to make a personal style ? Yet again, thank you!