fix: share button appearing in document preview and update element version number (MESSENGER-7666)

Riot/Modules/MatrixKit/Controllers/MXKPreviewViewController.m

@@ -76,6 +76,11 @@ Please see LICENSE in the repository root for full details.
     }
 }
 
+- (void)viewDidLoad
+{
+    self.view.backgroundColor = UIColor.clearColor;
+}
+
 - (IBAction)doneAction:(id)sender
 {
     [self dismissViewControllerAnimated:YES completion:^{