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In the Specify link keyword field, enter the message that is sent by the corresponding Link Zones command.
For players running presentations in BrightAuthor:connected 1.19.3 and BOS 9.0.101, Link Synchronize is the preferred method of synchronization instead of Link Zones.
For players on earlier software, Link Zones is still a valid method and Link Synchronize only works to synchronize content across multiple players.