The following updates are available for locked AT&T Surface Duos.
Software version
Update info
2021.419.71 (AT&T Locked Device)
This update:
Addresses scenarios outlined in the Android Security Bulletin — May 2021.
Improves device stability and UI stability.
Improves scenario when one screen would turn black while using Surface Duo in book mode.
Fixes scenario when a "Double-tap to switch screens" message was appearing in book mode.
Fixes the scenario when using the TalkBack with 3-button navigation where the list of recent apps was showing on the left screen when invoked from the right screen.
Source:
https://blogs.technet.microsoft.com/surface/2017/06/07/updates-for-surface-pro-3-06-june-2017/
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