You can change the speed of the Save/Open dialogs with Terminal. Enter this into Terminal to change the speed to the default:

defaults write NSGlobalDomain NSWindowResizeTime 0.2

Change the number at the end to speed up or slow down the animation. The following is practically instant:

defaults write NSGlobalDomain NSWindowResizeTime 0.001

You can change the speed of the Save/Open dialogs with Terminal. Enter this into Terminal to change the speed to the default:

defaults write NSGlobalDomain NSWindowResizeTime 0.2

Change the number at the end to speed up or slow down the animation. The following is practically instant:

defaults write NSGlobalDomain NSWindowResizeTime 0.001

This is not specific to the open/save dialog however, it reduces the time of all animations on the system that read this value.

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