Revise default theme

src/gui/Pages/AddChat/CreateRoom.qml

@@ -107,7 +107,7 @@ HBox {
         id: blockOtherServersCheckBox
         text: qsTr("Reject users from other matrix servers")
         subtitle.text: qsTr("Cannot be changed later!")
-        subtitle.color: theme.colors.middleBackground
+        subtitle.color: theme.colors.warningText
 
         Layout.fillWidth: true
     }

src/gui/Pages/AddChat/EncryptCheckBox.qml

@@ -8,7 +8,7 @@ HCheckBox {
     subtitle.text:
         qsTr("Only you and those you trust will be able to read the " +
              "conversation") +
-        `<br><font color="${theme.colors.middleBackground}">` +
+        `<br><font color="${theme.colors.warningText}">` +
         qsTr("Cannot be disabled later!") +
         "</font>"
     subtitle.textFormat: Text.StyledText