This page may help you: Clean the Cisco Webex Board Screen.
It says:
To clean the board's screen, wipe it with a soft dry cloth - a cleaning cloth is provided. Alternatively, you can also use any normal alcohol-based screen wipe.
The board is created for regular office use and is not intended for use in sterile environments. If you do want to disinfect your board, use isopropylalcohol. Do not disinfect the board's pens, because this might damage their tip.
Wayne
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