Keep mine adds your changes instead of replacing the other version

When your website is saved somewhere else while you edit it, Keep mine now puts your changes on top of that version instead of writing over it.

Keep mine — your edits are applied on top of the other version, so a section another tab or a colleague added stays. Where you both changed the same thing, yours wins. A change of yours to a section they removed can't be kept, and Seascape tells you how many.