Show current image from node editor on viewport's mesh I can't recall a feature in Blender where the user selects a node from material editor, presses a button and that node's image result will be shown on the mesh in the viewport. What is it and how to get it?
This, I believe, is a feature from the Node Wrangler addon

Never used it myself but it apparently creates a temporary emission shader to act as a texture viewer in the viewport.

Hotkey is Ctrl + Shift + Left Mouse button Click as illustrated in the wiki page by Greg Zaal.