fix: properly determine if WebContents is offscreen in WebContentsDelegate (backport: 3-1-x) (#16341)

atom/browser/common_web_contents_delegate.cc

@@ -163,7 +163,7 @@ void CommonWebContentsDelegate::InitWithWebContents(
   // Determien whether the WebContents is offscreen.
   auto* web_preferences = WebContentsPreferences::From(web_contents);
   offscreen_ =
-      !web_preferences || web_preferences->IsEnabled(options::kOffscreen);
+      web_preferences && web_preferences->IsEnabled(options::kOffscreen);
 
   // Create InspectableWebContents.
   web_contents_.reset(brightray::InspectableWebContents::Create(