From 1b1444f245f053ab517d481476270b8ac798a0d6 Mon Sep 17 00:00:00 2001
From: Abou Al Montacir <abou.almontacir@sfr.fr>
Date: Sat, 24 Jun 2023 10:50:28 +0200
Subject: [PATCH] GTK3: Fixed workarea handling on systems with frequent
 monitor removals. Closes: #40333. Thanks To: Anton Kavalenka.

Check number of connected monitors and fail if none.

Fall back to first monitory id no primary monitor is defined.
---
 lcl/interfaces/gtk3/gtk3winapi.inc | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/lcl/interfaces/gtk3/gtk3winapi.inc b/lcl/interfaces/gtk3/gtk3winapi.inc
index 2da3ed326b..6442a561ca 100644
--- a/lcl/interfaces/gtk3/gtk3winapi.inc
+++ b/lcl/interfaces/gtk3/gtk3winapi.inc
@@ -3949,6 +3949,11 @@ begin
     SPI_GETWORKAREA: begin
       pdisp:=TGdkDisplay.get_default;
       pmon:=pdisp^.get_primary_monitor();
+      if not Assigned(pmon) then begin
+        if pdisp^.get_n_monitors = 0 then
+          Exit(False);
+        pmon := pdisp^.get_monitor(0);
+      end;
       pmon^.get_workarea(@wa);
       pr:=PRect(pvParam);
       pr^.Left:=wa.x;