What's on the motherboard? Is it dangerous?

Question

motherboards

I'm assuming it's some kind of oxidation. Is it dangerous or is it okay? The computer works fine and is in perfect working order.

a photo

Answer 1

Not dangerous.
At the very least, do you have a warranty?

Answer 2

Disconnect from the mains
Remove the battery
Wipe with a damp cloth. It is better to use distilled or boiled water
Wipe with a dry cloth, dry with a hair dryer or wait 10 minutes
It will not be erased - repeat the same with alcohol.
Use further.