From 01e1248a98b71c7b760b2bcf541f94de4e4fa69d Mon Sep 17 00:00:00 2001
From: Craig Watson <craig@watsons.ch>
Date: Mon, 5 Sep 2016 19:42:10 -0400
Subject: [PATCH] Fix for cloned displays being considered as multiple displays
 on Linux

---
 src/core/UBDisplayManager.cpp | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/core/UBDisplayManager.cpp b/src/core/UBDisplayManager.cpp
index 8176da50..4b8e1e65 100644
--- a/src/core/UBDisplayManager.cpp
+++ b/src/core/UBDisplayManager.cpp
@@ -120,7 +120,16 @@ int UBDisplayManager::numScreens()
 {
     if (mUseMultiScreen)
     {
-        return mDesktop->screenCount();
+        int screenCount = mDesktop->screenCount();
+        // Some window managers report two screens when the two monitors are in "cloned" mode; this hack ensures
+        // that we consider this as just one screen.
+#ifdef Q_OS_LINUX
+        if (screenCount > 1
+            && (mDesktop->screenNumber(mDesktop->screen(0)) == mDesktop->screenNumber(mDesktop->screen(1))))
+            return 1;
+        else
+#endif
+            return screenCount;
     }
     else
     {