diff --git a/app/src/main/res/layout/activity_unsupported.xml b/app/src/main/res/layout/activity_unsupported.xml
index 7f94fc32f0..7c1308335b 100644
--- a/app/src/main/res/layout/activity_unsupported.xml
+++ b/app/src/main/res/layout/activity_unsupported.xml
@@ -11,7 +11,7 @@
         android:layout_marginTop="12dp"
         android:text="@string/app_crash"
         android:textAppearance="@style/TextAppearance.AppCompat.Medium"
-        android:textColor="?colorWarning"
+        android:textColor="?attr/colorWarning"
         android:textStyle="bold"
         app:layout_constraintStart_toStartOf="parent"
         app:layout_constraintTop_toTopOf="parent" />
diff --git a/app/src/main/res/layout/fragment_folders.xml b/app/src/main/res/layout/fragment_folders.xml
index 0fc79f6cf5..40d5d254f8 100644
--- a/app/src/main/res/layout/fragment_folders.xml
+++ b/app/src/main/res/layout/fragment_folders.xml
@@ -148,6 +148,6 @@
         android:layout_margin="@dimen/fab_padding"
         android:tint="@color/colorActionForeground"
         android:tooltipText="@string/title_compose"
-        app:backgroundTint="@color/lightColorWarning"
+        app:backgroundTint="@color/colorError"
         app:srcCompat="@drawable/baseline_warning_24" />
 </androidx.coordinatorlayout.widget.CoordinatorLayout>
diff --git a/app/src/main/res/layout/fragment_legend_messages.xml b/app/src/main/res/layout/fragment_legend_messages.xml
index ff35537031..9f34714d60 100644
--- a/app/src/main/res/layout/fragment_legend_messages.xml
+++ b/app/src/main/res/layout/fragment_legend_messages.xml
@@ -89,7 +89,7 @@
                 android:layout_height="wrap_content"
                 android:contentDescription="@string/title_legend_auth"
                 android:padding="12dp"
-                android:tint="?colorError"
+                android:tint="@color/colorError"
                 app:layout_constraintStart_toStartOf="parent"
                 app:layout_constraintTop_toBottomOf="@id/ivDraft"
                 app:srcCompat="@drawable/baseline_flag_24" />
diff --git a/app/src/main/res/layout/fragment_messages.xml b/app/src/main/res/layout/fragment_messages.xml
index 9dce23cb27..7cdb179156 100644
--- a/app/src/main/res/layout/fragment_messages.xml
+++ b/app/src/main/res/layout/fragment_messages.xml
@@ -288,5 +288,5 @@
         android:src="@drawable/baseline_warning_24"
         android:tint="@color/colorActionForeground"
         android:tooltipText="@string/title_compose"
-        app:backgroundTint="@color/lightColorWarning" />
+        app:backgroundTint="@color/colorError" />
 </androidx.coordinatorlayout.widget.CoordinatorLayout>
diff --git a/app/src/main/res/layout/fragment_options_misc.xml b/app/src/main/res/layout/fragment_options_misc.xml
index 8b9362054e..6f625ce480 100644
--- a/app/src/main/res/layout/fragment_options_misc.xml
+++ b/app/src/main/res/layout/fragment_options_misc.xml
@@ -113,7 +113,7 @@
                 android:layout_height="21dp"
                 android:contentDescription="@string/title_legend_auth"
                 android:src="@drawable/baseline_flag_24"
-                android:tint="?colorError"
+                android:tint="@color/colorError"
                 app:layout_constraintBottom_toBottomOf="@+id/swAuthentication"
                 app:layout_constraintStart_toStartOf="parent"
                 app:layout_constraintTop_toTopOf="@+id/swAuthentication" />
diff --git a/app/src/main/res/layout/include_message_compact.xml b/app/src/main/res/layout/include_message_compact.xml
index 4d99170d47..8323999ef4 100644
--- a/app/src/main/res/layout/include_message_compact.xml
+++ b/app/src/main/res/layout/include_message_compact.xml
@@ -122,7 +122,7 @@
         android:layout_marginStart="6dp"
         android:contentDescription="@string/title_legend_auth"
         android:src="@drawable/baseline_flag_24"
-        android:tint="?colorError"
+        android:tint="@color/colorError"
         app:layout_constraintBottom_toBottomOf="@+id/tvSubject"
         app:layout_constraintStart_toEndOf="@id/ivType"
         app:layout_constraintTop_toTopOf="@+id/tvSubject" />
diff --git a/app/src/main/res/layout/include_message_normal.xml b/app/src/main/res/layout/include_message_normal.xml
index be7101e4a9..11a94c2919 100644
--- a/app/src/main/res/layout/include_message_normal.xml
+++ b/app/src/main/res/layout/include_message_normal.xml
@@ -147,7 +147,7 @@
         android:layout_marginStart="6dp"
         android:contentDescription="@string/title_legend_auth"
         android:src="@drawable/baseline_flag_24"
-        android:tint="?colorError"
+        android:tint="@color/colorError"
         app:layout_constraintBottom_toBottomOf="@+id/tvFolder"
         app:layout_constraintStart_toEndOf="@id/ivType"
         app:layout_constraintTop_toTopOf="@+id/tvFolder" />
diff --git a/app/src/main/res/layout/item_nav.xml b/app/src/main/res/layout/item_nav.xml
index 9736b2cb53..2b8635970c 100644
--- a/app/src/main/res/layout/item_nav.xml
+++ b/app/src/main/res/layout/item_nav.xml
@@ -44,7 +44,7 @@
             android:layout_height="wrap_content"
             android:layout_marginEnd="12dp"
             android:src="@drawable/baseline_warning_24"
-            android:tint="@color/lightColorWarning"
+            android:tint="@color/colorError"
             app:layout_constraintBottom_toBottomOf="parent"
             app:layout_constraintEnd_toEndOf="parent"
             app:layout_constraintTop_toTopOf="parent" />
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
index 2e09ef9f47..8b902bcb15 100644
--- a/app/src/main/res/values/colors.xml
+++ b/app/src/main/res/values/colors.xml
@@ -5,6 +5,8 @@
     <color name="colorAccent">#ffb300</color>
     <color name="colorAccentDark">#b27d00</color>
 
+    <color name="colorError">#ff0000</color>
+
     <color name="blackPrimary">#026ca0</color>
     <color name="blackPrimaryDark">#004c7d</color>