[feature request] Configurable thumbnail size + retina thumbnails

Hi! Thank you for a great service, I bought Platinum the day I learned about you.

Currently, thumbnails are too small for me to figure out what's going on in the images. So I have to open many images in separate tabs just to see there is nothing interesting for me.

I suggest adding an option to increase the size of thumbnails.

Also, thumbnail images should be retina, at least 2x in linear dimensions compared to their CSS dimensions.

here's a userscript which implements configurable thumbnail size, at the cost of downloading the sample jpegs (800px):
https://gist.github.com/bipface/2c74b631d5936dfd458e5c50d3574e58

it should add a slider control to the navigation bar like so: https://i.imgur.com/iX5LMya.png
we've been using it as a workaround until the site implements such an enhancement itself
( thanks @fredgido )

Thank you! It's perfect.