Do you keep track of a "Parking Lot" for off topic items that are important?

Make sure that you cover as much of the agenda as possible within the timebox, and keep other topics to a minimum.

When you identify topics that do need to be hashed out, but are off topic and don't need to be covered in this meeting, keep track of them in a “Parking Lot”.

E.g. During the meeting you can call out “Off topic. I think that topic should be saved for the “Parking Lot”. Who is interested in joining that?”

See it in the video at around 9:00