@NorthernDawnArt
Probably not. The highest resolution images on Manebooru (search for * and then sort by pixels) are about 25000 x 10000 and do have colors (granted, not completely filling the canvas). The biggest images are about 100 MB (tad bit less, though) and mostly animated, though there are some static images that are pretty big.

Mostly this seems to be because of inefficient compression, though, they're only pretty high resolution (5000 x 6000 sort of size) when there are much larger (in terms of pixel count) images that are smaller, e.g. this image of the Great Seedling which is 15000 x 10000 but only 52 MB compared to this image of Trixie which is only about 4000 x 6000 but weighs in at 66 MB…

@Workable Goblin
Wonder if it'd break if this was filled with colors

The funny part is that it's trying to break the booru but it's only 118 kb because it's all white…

This… now this is beautiful. It should be featured

Best image on the site.

Amazing, breathtaking, beautiful.