Why does Cragmaw Hideout have dice on the map? Is this a normal roll20 thing?

Hope this is the right forum to ask this question. I'm fairly new to roll20, bought the Lost Mine of Phandelver module, and am getting ready to run the Cragmaw Hideout map. But for the life of me, I cannot understand why the map has three dice (multi-sided tokens) on the map, each with the numeral 4 displayed. I've read through all the module instructions and the map info, read through all the encounters. I don't know if this was an error by the designers, or if this signifies something I need to understand whenever I buy a D&D module.

Here is a snapshot from the map, showing two of the three dice. The third die is in a different, distant part of the map. I should clarify that these are not room numbers. Those are on the GM layer and in red circles. These dice are definitely something different.

Those are dice icons dragged from the chat window. Anyone might do that by accident, even a player. You can make a good guess as to the responsible party based on the color; I think it matches the player color. I've just checked, and they don't appear on my copy. My guess is that an errant mouse click dragged them onto the map.They can be safely deleted.

ok thank you very much