50501 (short for “50 protests, 50 states, 1 movement”) is an American progressivist grassroots political organization founded to protest the policies and actions of the second Donald Trump administration in the United States.

From wikipedia

The parade I assume is in reference to the birthday military parade for the 250th Army Anniversary of June 14, 2025. More here: wikipedia

You could try asking in !caffeitalia@feddit.it too, feddit.it is an italian speaking instance

I’m not sure if you are referring to this, but I’ve noticed some people overriding their comments after around 24h they have posted them - probably running an automated script. I assume they are doing it for perceived privacy reasons.