There was an event held, purportedly a Black Lives Matter group or sympathizer org, in a public park near me a few months ago. It was advertised as a protest. The park was dedicated to veterans, and featured a memorial monument at the entrance near a water feature. Veterans feared enough for the safety of the memorial that they felt the need to organize a group posted at the monument to prevent vandalism and destruction.
The promoters of the event on NextDoor were very open about their contempt for police and their supporters. They warned me that if I showed up, I would be taken care of. I have the screenshot to document the threat. NextDoor ignored their open threat and suspended me for asking obvious questions about what was being protested. Others who were concerned about the safety of the area, since this was organized right after several nights of violent demonstrations in our city, were also doxed and banned. You are not allowed to post about suspicious people or activities in your area, because you might inadvertently report a person of color, even if he is breaking into cars or destroying property.