From 7059aa83bcaecb0b1029f331f4d38229f84ed752 Mon Sep 17 00:00:00 2001
From: Brenden Matthews <github@brenden.brndn.io>
Date: Sat, 24 Feb 2024 16:31:07 -0500
Subject: [PATCH] Stop walking window tree if we get zero

It looks like some of the child windows are zero, which causes the next
call to XQueryTree to blow up.
---
 src/x11.cc | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/x11.cc b/src/x11.cc
index b1040fb21..6168c0e11 100644
--- a/src/x11.cc
+++ b/src/x11.cc
@@ -1384,8 +1384,13 @@ inline Window last_descendant(Display *display, Window parent) {
   while (
       XQueryTree(display, current, &_ignored, &_ignored, &children, &count) &&
       count != 0) {
-    current = children[count - 1];
+    auto next = children[count - 1];
     XFree(children);
+    if (next != 0) {
+      current = next;
+    } else {
+      break;
+    }
   }
 
   return current;