Add option to disable backfill read receipt bridging

config/bridge.go

@@ -74,6 +74,7 @@ type BridgeConfig struct {
 	ArchiveTag                    string `yaml:"archive_tag"`
 	PinnedTag                     string `yaml:"pinned_tag"`
 	TagOnlyOnCreate               bool   `yaml:"tag_only_on_create"`
+	MarkReadOnlyOnCreate          bool   `yaml:"mark_read_only_on_create"`
 
 	WhatsappThumbnail bool `yaml:"whatsapp_thumbnail"`
 

user.go

@@ -749,7 +749,7 @@ func (user *User) syncChatDoublePuppetDetails(doublePuppet *Puppet, chat Chat, j
 		return
 	}
 	intent := doublePuppet.CustomIntent()
-	if chat.UnreadCount == 0 {
+	if chat.UnreadCount == 0 && (justCreated || !user.bridge.Config.Bridge.MarkReadOnlyOnCreate) {
 		lastMessage := user.bridge.DB.Message.GetLastInChat(chat.Portal.Key)
 		if lastMessage != nil {
 			err := intent.MarkRead(chat.Portal.MXID, lastMessage.MXID)