With so many photos that are submitted uncropped, I usually have to zoom in to get a good look at a tiny insect. I often like to compare images side by side, either using the suggestions tab in the identify tool or by opening another browser window. The problem is that once you zoom in on an image and then move your mouse, it also moves the zoomed into location of the photo. That makes it impossible to zoom into the same central area of two images side by side.
It would be nice if the image viewer worked more like others where the zoom level and navigation of the zoomed in image worked independently from each other. Something similar to what Google Photos does, or any of the photo handling programs. Maybe an inset thumbnail navigation option, or requiring a click and drag operation to move the zoomed in image. Having the mouse wheel control the zoom level at the current pointer location and then having to click and drag to move around the zoomed in image works really well too.