Running custom functions on newly created Windows.
There are a class of questions along the lines of how do I do “X” when a window loads. Such as how does one start a window Maximized or start a window the top right corner. In these cases there is no default style that achieves this affect, so we need to use InitialMapCommand.
To start all xterms in the top right of the screen we can use AnimatedMove when the window loads to move the xterm to the desired place.
Style XTerm InitialMapCommand AnimatedMove -0 +0
To start chromium maximized just use the Maximze command.
Style chromium InitialMapCommand Maximize
This idea can be extended into various other applications of having a a window start in a specific state. Take note that there are some built in Styles that affect how applications start such as StartsIconic, StartsShaded, StartsOnPage, etc. InitialMap command is there for when there is no default Style to achieve the desired effect.