expressing your opinions or feelings in a loud and confident way (Oxford)
Vociferous people express their opinions and complaints loudly and repeatedly in speech, and vociferous demands, etc. are made repeatedly and loudly (Cambridge)
Opposition parties organized vociferous protests. (Oxford)
Local activist groups have become increasingly vociferous. (Cambridge)
vociferous protests
vociferous groups
Strident
Clamorous
Quiet
Silent
Vociferously