Whenever artboards are made in Photoshop, the crop tool no longer works. I made a document with about 5 artboards and I needed to crop a selection for a moment that I would undo shortly after. However every time I select the Crop Tool I instead get the Artboard Tool.
Documents with Artboards don't have a traditional canvas. The canvas of the entire project auto grows or contracts when Artboards are added or removed from the file. If you need to crop an Artboard, click on the edge to reveal the handles to redefine the bounds of an artboard.