Adding photos and videos · For guests
It says "Already added"
The same picture is already in the event, so it was skipped rather than stored twice.
Every upload is fingerprinted, and an identical file that is already in the event is skipped. This keeps the gallery clean when several guests share the same picture in a group chat and each uploads it.
A photo that has been edited, cropped or re-saved is a different file, so it uploads as a new one. Very large videos are not fingerprinted, so the same clip can be uploaded twice — ask the host to delete the extra.