Complex sentence: The convention announced plans to tighten security at its events in the wake of singer Christina Grimmie's shooting and the Orlando nightclub massacre, including adding metal detectors and security officers, and banning informal meet-and-greets between community members and YouTubers after panels.
Split into simpler sentences: The convention announced plans to tighten security at its events in the wake of singer Christina Grimmie's shooting and the Orlando nightclub massacre. Security measures included the addition of metal detectors, enhancing the number of security officers and banning informal meet-and-greets between community members and YouTubers after panels.