Tool-icon is a multi functional tool which appears as an icon either on the in the header of the tile when it is selected with mouse hover. It appears as three dots positioned vertically.
The tool-icon can be used to drag and drop a tile by hovering the mouse over it and dragging the child container to another position. On clicking, the tool-icon opens a context menu which by default, displays the options for hiding a tile or show all tiles.
The following GIF image shows the tool-icon operations for each tile.