As the owner or administrator of a group, you can choose to start an action while searching for files. You will find this selection window when you are in the search engine on the right-hand side of your screen: “Start an action”.
You can easily select “Edit category”, “Delete tags”, “Add tags”, “Add files to a group”, “Delete files from a group”, “Delete files”.
Press one of those actions.
Selection balls appear on the left side of the file name.
Select the balls for which you want to perform the action.
Click on “Continue with X files” at the bottom of the screen.
Perform the action that you want for those selected files by pressing “Adjust [action] for X files” at the bottom.
Congratulations! You have performed the chosen action for multiple files at the same time.