Thanks! I was inspired by your posts about video actually :)

I use ffmpeg or gif2webp, usually aiming for quality settings around 90~95, but sometimes it takes using the default quality settings and fudging around with parameters to get a reasonable filesize. In this case I went with lensdump instead of catbox.moe since it seems to load animated images faster.

Unfortunately we’re limited to .gif and .webp animated images instead of actual videos in order for thumbnails to work. If lemmy worked with .avif or .jxl that would be the best of all worlds.