PowerPoint does not enforce unique placeholder labels in a layout. Selecting a placeholder via its label using ph_location_label will throw an error, if the label is not unique. layout_dedupe_ph_labels helps to detect, rename, or delete duplicate placholder labels.
action: Action to perform on duplicate placeholder labels. One of:
detect (default) = show info on dupes only, make no changes
rename = create unique labels. Labels are renamed by appending a sequential number separated by dot to duplicate labels. For example, c("title", "title") becomes c("title.1", "title.2").
delete = only keep one of the placeholders with a duplicate label
print_info: Print action information (e.g. renamed placeholders) to console? Default is FALSE. Always TRUE for action detect.
Returns
A rpptx object (with modified placeholder labels).