[gnome-shell] screenshot: Enable opacity redirect for the panel

[Marge Bot <marge-bot src gnome org>]

commit 5b83ed59ddb4c32c4a844329fc6d85608c162ae8
Author: Ivan Molodetskikh <yalterz gmail com>
Date:   Mon Jan 31 10:58:49 2022 +0300

    screenshot: Enable opacity redirect for the panel
    
    This makes the panel look correct when it fades out (e.g. while dragging
    the area selection around or while the screenshot UI is fading in and
    out).
    
    Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2138>

 js/ui/screenshot.js | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/js/ui/screenshot.js b/js/ui/screenshot.js
index 5c338120e1..56f3cab7f1 100644
--- a/js/ui/screenshot.js
+++ b/js/ui/screenshot.js
@@ -1081,6 +1081,7 @@ var ScreenshotUI = GObject.registerClass({
             y_align: Clutter.ActorAlign.END,
             y_expand: true,
             vertical: true,
+            offscreen_redirect: Clutter.OffscreenRedirect.AUTOMATIC_FOR_OPACITY,
         });
         this._primaryMonitorBin.add_child(this._panel);