The limit was overly conservative and bookmark exhaustion may occur on realistic documents. The increased limit allows documents with much greater depth to be safely processed. The limit is increased from 100 to 10,000. Developed in https://github.com/WordPress/wordpress-develop/pull/10820. Follow-up to [61755]. Props jonsurrell, dmsnell, westonruter. See #64394. Built from https://develop.svn.wordpress.org/trunk@61756 git-svn-id: http://core.svn.wordpress.org/trunk@61062 1a063a9b-81f0-0310-95a4-ce76da25c4cd