In terms of applicaton signatures, please keep in mind as well that while Application providers (Facebook, ....) strive to provide a constant look and feel across various platforms, the actual underlying implementations very significantly from one platform to another. This is due to the characteristics of the underlying OS, APIs and mechanism available, content delivery capabilities and restrictions, commercial agreements and sometimes just software maintenance changes, the application streams will vary significantly from one platform to another - mostly invisible to the end user. We strive to keep our signature sets as accurate as possible and rollout new updates when available in the AP firmware. Latest signature sets have been rolled out with ExtremeWireless(TM) 10.21.01.
The latest ExtremeCloud(TM) 3.21.03 upgrade is currently rolling out the upgrade of managed and supported access points to ExtremeWireless v10.21.02. May take several days for all APs to be at that newer release (from 10.04.01). Please check the version of your managed AP and try again once your APs are at the latest firmware revision.