PSA for HD. If you plan on having any heavy light fixtures installed, have the electricians install metal boxes for that location or a metal Fan support box that fits on the bottom of a ceiling beam.
Last night the light fixture in our entryway fell out of the ceiling and smashed into the floor. The plastic junction box it was mounted, broke apart. Luckely no one was close, we were across the living room when it fell. The light fixture was really heavy, the idiot that installed it should have known better.