make it opt-in, not opt-out

Already have it enabled through 4chanX, although I guess not everybody has it installed.

>>852
yeah i don't use 4chanx

In Vichan this option as you describe it exists. However I'm trying to escape vichan so the opt out feature would need to be designed when I'm in a good position with that. you should know that this permanently modifies the thumbnail so that people who are not running javascript will have no way to undo it. This means that everything I program will have to be done with the assumption that all gifs autoplay. This also means that thumbnails for gifs are 8x larger. A concern to consider.

Vichan, when you say you don't want it, grabs a frame from the autoplay gif and creates a new display element for it. I assume that 4chanX is loading the full gif on every single image(hence the concerns about lazy loading).
It would be low priority if wanted.