OptionalactiveAdd-in custom data
Add-in enabled states
OptionalbackgroundBackground pages (images / PDF pages)
Serialized Fabric.js canvas data
Last used brush color
OptionaleventsPersistent audit log — captured by useWhiteboardSync on every
observed change (local + remote) and rolled into the file at save
time. Append-only. Capped at ~10K entries with a __truncated__
sentinel inserted at the head when older entries are dropped.
Pre-existing files (created before this field) load with an
empty log and audit from that point forward.
ISO timestamp of last modification
File display name
User ID of the owner
Index of the active background page, or undefined for no background