We have updated the keyboard shortcuts in QGIS to make it more efficient to carry out repetitive tasks.
ctrl-d - Remove selected layers in table of contents> - Select next vertex when using the node tool< - Select previous vertex when using the node toolDelete or Backspace - delete the selected features (you can undo these actions), or a node when using the nodetool.F5 updates the canvas (instead of ctrl-r)See also Issue 9094 and Pull Request 1010 for more details.