In case you're not clear on this point:
DON'T FLY INDOORS!
After you've flown it a thousand times and have gotten really good, then don't fly it indoors.
If you've watched hundreds of YouTube videos of other people flying indoors easily, then don't fly it indoors.
If your friend flies it all the time successfully indoors, then don't fly it indoors.
If you are specifically trying to wreck your mavic and damage the inside of your house, THEN you can fly it indoors.
If it has been raining outside for weeks and you just have to discharge the batteries, then don't fly it indoors.
If you get full GPS signal strength in your house, then don't fly it indoors.
If some users on this forum say they fly it indoors all the time with no problem, then don't fly it indoors.
If Mother Mary appears to you in a dream and tells you to fly it indoors, then don't fly it indoors.
If you just want to hover briefly in your living room at a low altitude, then don't fly it indoors.
If you are elected "The Greatest Mavic Pilot to Ever Live", then don't fly it indoors.
Having said all that, try whatever you want.
After you fly it indoors, please post a reply to this thread about your crash so we can say "I told you so." Pictures are welcome.