diff --git a/libdino/src/entity/conversation.vala b/libdino/src/entity/conversation.vala
index 585db07e..145dc977 100644
--- a/libdino/src/entity/conversation.vala
+++ b/libdino/src/entity/conversation.vala
@@ -105,10 +105,12 @@ public class Conversation : Object {
         Xmpp.XmppStream? stream = stream_interactor.get_stream(account);
         if (!Application.get_default().settings.notifications) return NotifySetting.OFF;
         if (type_ == Type.GROUPCHAT) {
-            Xmpp.Xep.Muc.Flag flag = stream.get_flag(Xmpp.Xep.Muc.Flag.IDENTITY);
+            Xmpp.Xep.Muc.Flag? flag = stream.get_flag(Xmpp.Xep.Muc.Flag.IDENTITY);
             if (flag != null) {
                 bool members_only = flag.has_room_feature(counterpart.bare_jid, Xmpp.Xep.Muc.Feature.MEMBERS_ONLY);
                 return members_only ? NotifySetting.ON : NotifySetting.HIGHLIGHT;
+            } else {
+                return NotifySetting.OFF;
             }
         }
         return NotifySetting.ON;
diff --git a/libdino/src/service/connection_manager.vala b/libdino/src/service/connection_manager.vala
index 977fc732..ad846ba2 100644
--- a/libdino/src/service/connection_manager.vala
+++ b/libdino/src/service/connection_manager.vala
@@ -232,7 +232,7 @@ public class ConnectionManager : Object {
 
     private void check_reconnect(Account account) {
         bool acked = false;
-        DateTime? last_activity_was = connections[account].last_activity != null ? connections[account].last_activity : null;
+        DateTime? last_activity_was = connections[account].last_activity;
 
         XmppStream stream = connections[account].stream;
         stream.get_module(Xep.Ping.Module.IDENTITY).send_ping(stream, account.bare_jid.domain_jid, () => {
diff --git a/main/src/ui/conversation_titlebar/view.vala b/main/src/ui/conversation_titlebar/view.vala
index cb31527e..9706b516 100644
--- a/main/src/ui/conversation_titlebar/view.vala
+++ b/main/src/ui/conversation_titlebar/view.vala
@@ -22,7 +22,6 @@ public class ConversationTitlebar : Gtk.Box {
     }
 
     private StreamInteractor stream_interactor;
-    private Conversation? conversation;
 
     private Box content_box = new Box(Orientation.HORIZONTAL, 0) { margin=5, margin_start=15, margin_end=5, hexpand=true, visible=true };
     private Label title_label = new Label("") { visible=true };
diff --git a/main/src/ui/conversation_titlebar/view_csd.vala b/main/src/ui/conversation_titlebar/view_csd.vala
index 83a1a474..26231a4c 100644
--- a/main/src/ui/conversation_titlebar/view_csd.vala
+++ b/main/src/ui/conversation_titlebar/view_csd.vala
@@ -9,7 +9,6 @@ public class ConversationTitlebarCsd : Gtk.HeaderBar {
 
     private StreamInteractor stream_interactor;
     private Window window;
-    private Conversation? conversation;
 
     public ConversationTitlebarCsd(StreamInteractor stream_interactor, Window window) {
         this.stream_interactor = stream_interactor;
diff --git a/main/src/ui/manage_accounts/add_account_dialog.vala b/main/src/ui/manage_accounts/add_account_dialog.vala
index 97a8e924..558738aa 100644
--- a/main/src/ui/manage_accounts/add_account_dialog.vala
+++ b/main/src/ui/manage_accounts/add_account_dialog.vala
@@ -215,7 +215,7 @@ public class AddAccountDialog : Gtk.Dialog {
     private async void on_sign_in_jid_continue_button_clicked() {
         Jid jid = new Jid(jid_entry.get_text());
         sign_in_jid_continue_stack.visible_child_name = "spinner";
-        Register.ServerAvailabilityReturn server_status = yield stream_interactor.get_module(Register.IDENTITY).check_server_availability(jid);
+        Register.ServerAvailabilityReturn server_status = yield Register.check_server_availability(jid);
         sign_in_jid_continue_stack.visible_child_name = "label";
         if (server_status.available) {
             show_sign_in_password();
diff --git a/main/src/ui/manage_accounts/dialog.vala b/main/src/ui/manage_accounts/dialog.vala
index a86a8346..07656f3a 100644
--- a/main/src/ui/manage_accounts/dialog.vala
+++ b/main/src/ui/manage_accounts/dialog.vala
@@ -195,7 +195,7 @@ public class Dialog : Gtk.Dialog {
         active_switch.set_active(account.enabled);
         jid_label.label = account.bare_jid.to_string();
 
-        alias_hybrid.text = account.alias;
+        alias_hybrid.text = account.alias ?? "";
         password_hybrid.entry.input_purpose = InputPurpose.PASSWORD;
         password_hybrid.text = account.password;