Preview for shading texture nodes as backdrop, as in compositor

Many people ask for a way to quickly visualize 2d texture, so why not borrow the functionality from the compositor and add a backdrop image in the shader editor? Possible addiotions would be size and position of the preview, normalization (in case the texture has values below 0 or over 1).

In the screenshot the backdrop preview is relative to the currently selected node, which could be the way to tell blender what texture you want to preview. When no RGB/value node is selected or no node is selected at all, the preview could just disappear.