If you press or release the option key while viewing FlowJo menus, some of the items may change! This quickly lets you know what different operations are accessible from the menu while holding down the option key.

• Using Next/Previous graph. If you hold down the option key while performing these operations, every open graph window is cycled to the next or previous sample.
• Copying a graph. When you copy a graph from a graph window and hold down the option key, then FlowJo will also copy any gates (polygons, etc.) that are shown on the graph (this may occur anyway depending on your preference settings).
• Creating a new gate. When you are asked for the name of a new subpopulation (you just drew a gate on a graph), you can hold down the option key while pressing "OK" or "Select". In either case, the graph window on which you just created the new gate will be closed. (In the case of "Select", a new window containing the subpopulation you created will now be opened).
• Navigating the gating hierarchy. If you hold down the option key while clicking on the "Show parent" or "Show child" buttons in the graph window (the up and down arrows, respectively), then the current window is closed before the other one is opened.
• Changing the graph characteristics. If you hold down the option key while changing the characteristics of the graph (i.e., dot plot, contour plot, density plot, or contour levels, or smoothing, or outliers), then the same change will be applied to all open graph windows (for that workspace).  This is true either while selecting the menu command (from the "Graph" menu), or while clicking on the "Apply" button in the graph tools window.
• Closing a plot. If you hold down the option key while clicking on the close box of a graph, then all of the open graph windows (for that workspace) will also be closed.
• Creating a gate. If you hold down the option key while clicking in a two-dimensional graph, then you will create a rectangular gate rather than a polygon.
• Showing/Hiding gating hierarchy. If you hold down the option key while clicking on a disclosure triangle in the workspace window (next to the node name), then the show or hide function will be applied to all "children" of that node (i.e., collapse/expand the entire tree). Alternatively, if you hold down the command key while clicking on a triangle, then the show or hide function is applied to all "siblings" (all other nodes at that level).
• Opening or changing other graphs (under the Graph Menu). Holding down the option key keeps FlowJo from confirming this option.
• Duplicating draw objects in the Layout Editor.  Holding down the option key while dragging an objects will create a duplicate of the object in the new location.
• Removing a layer from an overlay.  Holding the option key while passing the cursor over the legend of a multi-layer overlay shows the cursor as a trash can.  Option-clicking a row in the legend will remove that layer from the plot.