As a facilitator, I would like to have a timer so that participants know, how much time is left on the current task.

• The timer should show minutes and seconds remaining.
• At 1 minute left, there should be a visible reminder that time is running out
• When the timer runs out, there should be a visible signal. An audio signal would be great.
• a useful but optional feature for a first iteration could be a set of presets (like 1 min, 5 min, 15 min)

You could use the implementation in mural as inspiration

By having multiple pages for Whiteboard, the erase can continue the discussion in different pages and refer back to initial pages, instead eof rasing them.