I know it's bad form to submit a large PR like this but this fixes almost everything in https://github.com/firefly-iii/firefly-iii/issues/9183 and I was too lazy to create a branch for it.

app/Events/Security/DisabledMFA.php

@@ -0,0 +1,43 @@
+<?php
+/*
+ * EnabledMFA.php
+ * Copyright (c) 2024 james@firefly-iii.org.
+ *
+ * This file is part of Firefly III (https://github.com/firefly-iii).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see https://www.gnu.org/licenses/.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Events\Security;
+
+use FireflyIII\Events\Event;
+use FireflyIII\User;
+use Illuminate\Contracts\Auth\Authenticatable;
+use Illuminate\Queue\SerializesModels;
+
+class DisabledMFA extends Event
+{
+    use SerializesModels;
+
+    public User $user;
+
+    public function __construct(null|Authenticatable|User $user)
+    {
+        if ($user instanceof User) {
+            $this->user = $user;
+        }
+    }
+}

app/Events/Security/EnabledMFA.php

@@ -0,0 +1,43 @@
+<?php
+/*
+ * EnabledMFA.php
+ * Copyright (c) 2024 james@firefly-iii.org.
+ *
+ * This file is part of Firefly III (https://github.com/firefly-iii).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see https://www.gnu.org/licenses/.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Events\Security;
+
+use FireflyIII\Events\Event;
+use FireflyIII\User;
+use Illuminate\Contracts\Auth\Authenticatable;
+use Illuminate\Queue\SerializesModels;
+
+class EnabledMFA extends Event
+{
+    use SerializesModels;
+
+    public User $user;
+
+    public function __construct(null|Authenticatable|User $user)
+    {
+        if ($user instanceof User) {
+            $this->user = $user;
+        }
+    }
+}

app/Events/Security/MFABackupFewLeft.php

@@ -0,0 +1,45 @@
+<?php
+/*
+ * EnabledMFA.php
+ * Copyright (c) 2024 james@firefly-iii.org.
+ *
+ * This file is part of Firefly III (https://github.com/firefly-iii).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see https://www.gnu.org/licenses/.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Events\Security;
+
+use FireflyIII\Events\Event;
+use FireflyIII\User;
+use Illuminate\Contracts\Auth\Authenticatable;
+use Illuminate\Queue\SerializesModels;
+
+class MFABackupFewLeft extends Event
+{
+    use SerializesModels;
+
+    public User $user;
+    public int $count;
+
+    public function __construct(null|Authenticatable|User $user, int $count)
+    {
+        if ($user instanceof User) {
+            $this->user = $user;
+        }
+        $this->count = $count;
+    }
+}

app/Events/Security/MFABackupNoLeft.php

@@ -0,0 +1,43 @@
+<?php
+/*
+ * EnabledMFA.php
+ * Copyright (c) 2024 james@firefly-iii.org.
+ *
+ * This file is part of Firefly III (https://github.com/firefly-iii).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see https://www.gnu.org/licenses/.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Events\Security;
+
+use FireflyIII\Events\Event;
+use FireflyIII\User;
+use Illuminate\Contracts\Auth\Authenticatable;
+use Illuminate\Queue\SerializesModels;
+
+class MFABackupNoLeft extends Event
+{
+    use SerializesModels;
+
+    public User $user;
+
+    public function __construct(null|Authenticatable|User $user)
+    {
+        if ($user instanceof User) {
+            $this->user = $user;
+        }
+    }
+}

app/Events/Security/MFANewBackupCodes.php

@@ -0,0 +1,43 @@
+<?php
+/*
+ * EnabledMFA.php
+ * Copyright (c) 2024 james@firefly-iii.org.
+ *
+ * This file is part of Firefly III (https://github.com/firefly-iii).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see https://www.gnu.org/licenses/.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Events\Security;
+
+use FireflyIII\Events\Event;
+use FireflyIII\User;
+use Illuminate\Contracts\Auth\Authenticatable;
+use Illuminate\Queue\SerializesModels;
+
+class MFANewBackupCodes extends Event
+{
+    use SerializesModels;
+
+    public User $user;
+
+    public function __construct(null|Authenticatable|User $user)
+    {
+        if ($user instanceof User) {
+            $this->user = $user;
+        }
+    }
+}

app/Events/Security/MFAUsedBackupCode.php

@@ -0,0 +1,43 @@
+<?php
+/*
+ * EnabledMFA.php
+ * Copyright (c) 2024 james@firefly-iii.org.
+ *
+ * This file is part of Firefly III (https://github.com/firefly-iii).
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see https://www.gnu.org/licenses/.
+ */
+
+declare(strict_types=1);
+
+namespace FireflyIII\Events\Security;
+
+use FireflyIII\Events\Event;
+use FireflyIII\User;
+use Illuminate\Contracts\Auth\Authenticatable;
+use Illuminate\Queue\SerializesModels;
+
+class MFAUsedBackupCode extends Event
+{
+    use SerializesModels;
+
+    public User $user;
+
+    public function __construct(null|Authenticatable|User $user)
+    {
+        if ($user instanceof User) {
+            $this->user = $user;
+        }
+    }
+}