Issue 7691: We can now switch to BCC for ActivityPub

src/Protocol/ActivityPub/Transmitter.php

@@ -363,6 +363,10 @@ class Transmitter
 			}
 		}
 
+		if (Config::get('system', 'ap_always_bcc')) {
+			$always_bcc = true;
+		}
+
 		if (self::isAnnounce($item) || Config::get('debug', 'total_ap_delivery')) {
 			// Will be activated in a later step
 			$networks = Protocol::FEDERATED;

static/defaults.config.php

@@ -59,6 +59,10 @@ return [
 		// Only show small preview pictures.
 		'always_show_preview' => false,
 
+		// ap_always_bcc (Boolean)
+		// Adressing receivers via ActivityPub by BCC. Increases privacy, decreases performnce.
+		'ap_always_bcc' => false,
+
 		// archival_days (Integer)
 		// Number of days that we try to deliver content before we archive a contact.
 		'archival_days' => 32,