     ///
     open var caption: NSAttributedString? {
         didSet {
-            styledCaption = applyCaptionAppearance(to: caption)
+            styledCaptionCache = nil
         }
     }
 

        willSet {
            if newValue != alignment {
                glyphImage = nil
            }
        }
    }


    /// Attachment's Caption String, with MediaAttachment's appearance attributes applied.
    ///
    private var styledCaptionCache: NSAttributedString?

    /// Returns the cached caption (with our custom attributes applied), or regenerates the Styled Caption, if needed.
    ///
    private var styledCaption: NSAttributedString? {
        if let caption = styledCaptionCache {
            return caption
        }

        styledCaptionCache = applyCaptionAppearance(to: caption)
        return styledCaptionCache
    }


    /// Creates a new attachment
