Today, Facebook has announced a few changes to their photo viewer. Now, when you click on a photo it will automatically open up in the photo viewer in the highest resolution possible. This can be up to four times as big as before the update.
Here's how Facebook's Ryan Mack, who began the photo-viewer-improving project as part of a "Hackamonth," describes the issue:
The internet standard color profile is called "sRGB." Every photo on Facebook and most of the internet uses the sRGB profile. For some reason most web browsers don't assume the image is sRGB, and you actually have to redefine sRGB in every single image. Our photos software was already quite capable of defining sRGB in every image, but that definition was pretty big, and turning it on would have slowed down page loading.
The standard sRGB definition was 3KB. That's not a big deal for large images, but our thumbnails in newsfeed and timeline are pretty small. Adding the standard definition can slow down loading by up to 30%. Now my quest had become making the sRGB definition smaller.
So they did. You can read more about how at the Facebook Engineering blog.
Another improvement to Facebook's photo viewer makes it possible to view photos in fullscreen. There will now be a set of arrows at the top right corner of photos that will allow you to expand them. There is one caveat, however. This will only work in the latest versions of Chrome and Firefox.
As you have probably noticed, Facebook's photo viewer has gone through a bit of a redesign over the last couple of months.