diff --git a/app/src/main/java/com/nextcloud/talk/controllers/ContactsController.java b/app/src/main/java/com/nextcloud/talk/controllers/ContactsController.java
index 0537a8ffe..fc9d2d8ce 100644
--- a/app/src/main/java/com/nextcloud/talk/controllers/ContactsController.java
+++ b/app/src/main/java/com/nextcloud/talk/controllers/ContactsController.java
@@ -62,7 +62,6 @@ import com.nextcloud.talk.models.json.autocomplete.AutocompleteUser;
 import com.nextcloud.talk.models.json.conversations.Conversation;
 import com.nextcloud.talk.models.json.conversations.RoomOverall;
 import com.nextcloud.talk.models.json.converters.EnumActorTypeConverter;
-import com.nextcloud.talk.models.json.converters.EnumParticipantTypeConverter;
 import com.nextcloud.talk.models.json.participants.Participant;
 import com.nextcloud.talk.utils.ApiUtils;
 import com.nextcloud.talk.utils.ConductorRemapping;
diff --git a/app/src/main/java/com/nextcloud/talk/controllers/ConversationInfoController.kt b/app/src/main/java/com/nextcloud/talk/controllers/ConversationInfoController.kt
index a73fb367d..6dee8e4ae 100644
--- a/app/src/main/java/com/nextcloud/talk/controllers/ConversationInfoController.kt
+++ b/app/src/main/java/com/nextcloud/talk/controllers/ConversationInfoController.kt
@@ -715,7 +715,8 @@ class ConversationInfoController(args: Bundle) : BaseController(args), FlexibleA
         }
 
         if (participant.type == Participant.ParticipantType.MODERATOR ||
-            participant.type == Participant.ParticipantType.GUEST_MODERATOR) {
+            participant.type == Participant.ParticipantType.GUEST_MODERATOR
+        ) {
             ncApi.demoteAttendeeFromModerator(
                 credentials,
                 ApiUtils.getUrlForRoomModerators(
@@ -729,7 +730,8 @@ class ConversationInfoController(args: Bundle) : BaseController(args), FlexibleA
                 .observeOn(AndroidSchedulers.mainThread())
                 .subscribe(subscriber)
         } else if (participant.type == Participant.ParticipantType.USER ||
-            participant.type == Participant.ParticipantType.GUEST) {
+            participant.type == Participant.ParticipantType.GUEST
+        ) {
             ncApi.promoteAttendeeToModerator(
                 credentials,
                 ApiUtils.getUrlForRoomModerators(
diff --git a/app/src/main/java/com/nextcloud/talk/controllers/bottomsheet/OperationsMenuController.java b/app/src/main/java/com/nextcloud/talk/controllers/bottomsheet/OperationsMenuController.java
index 3cea909e9..69811b8d9 100644
--- a/app/src/main/java/com/nextcloud/talk/controllers/bottomsheet/OperationsMenuController.java
+++ b/app/src/main/java/com/nextcloud/talk/controllers/bottomsheet/OperationsMenuController.java
@@ -54,7 +54,6 @@ import com.nextcloud.talk.models.json.capabilities.Capabilities;
 import com.nextcloud.talk.models.json.capabilities.CapabilitiesOverall;
 import com.nextcloud.talk.models.json.conversations.Conversation;
 import com.nextcloud.talk.models.json.conversations.RoomOverall;
-import com.nextcloud.talk.models.json.generic.GenericOverall;
 import com.nextcloud.talk.models.json.participants.AddParticipantOverall;
 import com.nextcloud.talk.utils.ApiUtils;
 import com.nextcloud.talk.utils.ConductorRemapping;
diff --git a/app/src/main/java/com/nextcloud/talk/models/json/converters/EnumActorTypeConverter.kt b/app/src/main/java/com/nextcloud/talk/models/json/converters/EnumActorTypeConverter.kt
index 22fcf6c21..ca7407a36 100644
--- a/app/src/main/java/com/nextcloud/talk/models/json/converters/EnumActorTypeConverter.kt
+++ b/app/src/main/java/com/nextcloud/talk/models/json/converters/EnumActorTypeConverter.kt
@@ -2,7 +2,9 @@
  * Nextcloud Talk application
  *
  * @author Joas Schilling
+ * @author Andy Scherzinger
  * Copyright (C) 2021 Joas Schilling <coding@schilljs.com>
+ * Copyright (C) 2021 Andy Scherzinger <info@andy-scherzinger.de>
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -30,12 +32,12 @@ import com.nextcloud.talk.models.json.participants.Participant.ActorType.USERS
 
 class EnumActorTypeConverter : StringBasedTypeConverter<Participant.ActorType>() {
     override fun getFromString(string: String): Participant.ActorType {
-        when (string) {
-            "emails" -> return EMAILS
-            "groups" -> return GROUPS
-            "guests" -> return GUESTS
-            "users" -> return USERS
-            else -> return DUMMY
+        return when (string) {
+            "emails" -> EMAILS
+            "groups" -> GROUPS
+            "guests" -> GUESTS
+            "users" -> USERS
+            else -> DUMMY
         }
     }
 
@@ -45,12 +47,12 @@ class EnumActorTypeConverter : StringBasedTypeConverter<Participant.ActorType>()
             return ""
         }
 
-        when (`object`) {
-            EMAILS -> return "emails"
-            GROUPS -> return "groups"
-            GUESTS -> return "guests"
-            USERS -> return "users"
-            else -> return ""
+        return when (`object`) {
+            EMAILS -> "emails"
+            GROUPS -> "groups"
+            GUESTS -> "guests"
+            USERS -> "users"
+            else -> ""
         }
     }
 }
diff --git a/app/src/main/java/com/nextcloud/talk/models/json/participants/Participant.java b/app/src/main/java/com/nextcloud/talk/models/json/participants/Participant.java
index 587e33810..71a9db829 100644
--- a/app/src/main/java/com/nextcloud/talk/models/json/participants/Participant.java
+++ b/app/src/main/java/com/nextcloud/talk/models/json/participants/Participant.java
@@ -24,7 +24,6 @@ import com.bluelinelabs.logansquare.annotation.JsonField;
 import com.bluelinelabs.logansquare.annotation.JsonObject;
 import com.nextcloud.talk.models.json.converters.EnumActorTypeConverter;
 import com.nextcloud.talk.models.json.converters.EnumParticipantTypeConverter;
-import com.nextcloud.talk.models.json.converters.EnumSystemMessageTypeConverter;
 import com.nextcloud.talk.models.json.converters.ObjectParcelConverter;
 
 import org.parceler.Parcel;