Require textFormat declaration for all Text elements.

shell/plugins/osd/Osd.qml

@@ -159,6 +159,7 @@ Item {
           width: root.iconWidth
           height: parent.height
           Text {
+            textFormat: Text.PlainText
             // Sit the glyph's ink flush in the column, centered when the
             // column is wider than this particular glyph.
             x: Math.round((root.iconWidth - root.iconInkWidth) / 2 - iconMetrics.tightBoundingRect.x)
@@ -186,6 +187,7 @@ Item {
           }
         }
         Text {
+          textFormat: Text.PlainText
           visible: root.message !== ""
           width: root.hasProgress ? root.valueWidth : root.messageWidth
           // The readout hugs the card edge so a short percentage doesn't leave