Selects completely hidden objects that do not affect the visual appearance of the PDF, such as redundant objects that were left behind on a hidden layer or original cropped content that is of no use.
Hidden objects can increase the file size, add to the file complexity and they may produce false hits during preflight. Therefore, you may want to use this Action to select these unneeded objects and ignore or remove them before preflighting the document.
Note that there are different options to determine whether or not an object is visible; you have the choice whether or not to take into account the objects on other layers, or you can limit the scope by adding another select Action.
Select concealed objects Remove selection