Heyo, just some stuff I noticed that might be useful (or maybe it's old news already) that I didn't see on the wiki page. I don't want to edit it because I'm not fully certain about this stuff.
Seems to be allowing images greater than 1280x again.
If you just right click -> view image, you'll be taken to the standard 1280, but if you left click a significantly larger image pops up. This only seems to apply to posts made a month or two ago and to my knowledge is not retroactive.
I use Image Max URL addon for Firefox and it doesn't catch that particular redirect. ("Image Max URL works by replacing URLs, and in some cases, querying website-specific APIs.")
Possible way to get a higher resolution.
Clicking the little + magnification icon takes me to a highly compressed 71 kb version [I'd put links here, but these appear to be temporary links that expire quickly], but the addon I mentioned earlier redirects me to a 1302 kb version of the same resolution, but with far less compression artifacts. I'm assuming this is that API query thing they mention; I'm not really code savvy. This is nowhere near the original (inaccessible) file, but it could be useful if the artist does not allow downloads and there are no other sources.
A note of caution though, the redirects seem a bit finnicky and on rare occasion redirect to an image of worse quality.
Anyways, that's about it; just throwing some info out there in case someone finds it useful.