In Lightroom DEVELOP the image does not copy from before to after after using the buttons below.
Could you please let me know the version of Lightroom installed on your computer ?
Also which operating system are you working on , Windows or MAC ?
Is it possible LR is showing Before and After as the same?
Clicking a button with > < can make them the same.
You can reset the "Before" state of a photo by a Right-click on a step in the History Panel.
Press the [ \ ] to also get a "Before" view.
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