Aseprite XWayland fixes: color picker crash + popup closing + capture release

aseprite-xwayland.patch

diff --git a/src/app/ui/popup_window_pin.cpp b/src/app/ui/popup_window_pin.cpp
index dc3f839a0..6ed26f082 100644
--- a/src/app/ui/popup_window_pin.cpp
+++ b/src/app/ui/popup_window_pin.cpp
@@ -62,6 +62,15 @@ bool PopupWindowPin::onProcessMessage(Message* msg)
         m_pinned = false;
       break;
     }
+
+    // Don't close this popup when the mouse moves outside the hot
+    // region. This kind of popup (color picker, etc.) should only
+    // close on explicit actions: clicking outside, pressing
+    // Escape/Enter, or closing via the close button.
+    case kMouseMoveMessage:
+      if (!m_pinned)
+        return Window::onProcessMessage(msg);
+      break;
   }
 
   return PopupWindow::onProcessMessage(msg);
diff --git a/src/ui/manager.cpp b/src/ui/manager.cpp
index 8d2e6f962..605d60cd4 100644
--- a/src/ui/manager.cpp
+++ b/src/ui/manager.cpp
@@ -461,12 +461,19 @@ void Manager::generateMessagesFromOSEvents()
         break;
       }
 
-      case os::Event::WindowLeave:
+      case os::Event::AppLeave:
+        // Release capture only when focus leaves the application
+        // entirely (e.g. Alt+Tab to another app). We don't release
+        // on WindowLeave because on XWayland the compositor can
+        // send spurious FocusOut events that would prematurely
+        // release capture and close popup windows (e.g. the color
+        // picker popup).
         if (capture_widget) {
-          const gfx::Point mousePos = display->nativeWindow()->pointFromScreen(
+          Display* captureDisplay = capture_widget->display();
+          const gfx::Point mousePos = captureDisplay->nativeWindow()->pointFromScreen(
             get_mouse_position());
           auto* msg = newMouseMessage(kMouseUpMessage,
-                                      display,
+                                      captureDisplay,
                                       nullptr,
                                       mousePos,
                                       PointerType::Unknown,
diff --git a/laf/os/x11/system.h b/laf/os/x11/system.h
index c8c1ef5..2cb358e 100644
--- a/laf/os/x11/system.h
+++ b/laf/os/x11/system.h
@@ -14,6 +14,8 @@
 #include "os/x11/screen.h"
 #include "os/x11/x11.h"
 
+#include <algorithm>
+
 #include <X11/Xlib.h>
 #include <X11/Xutil.h>
 #include <X11/extensions/Xrandr.h>
@@ -65,19 +67,42 @@ public:
     int screen = XDefaultScreen(display);
     ::Window root = XRootWindow(display, screen);
 
+    // Clamp coordinates to the root window bounds to avoid
+    // X11 BadMatch error when picking colors outside the screen
+    // (e.g. when dragging the color picker outside the window on
+    // XWayland or multi-monitor setups). See aseprite/aseprite#5469.
+    XWindowAttributes rootAttrs;
+    if (!XGetWindowAttributes(display, root, &rootAttrs))
+      return gfx::ColorNone;
+
+    int x = std::clamp(screenPosition.x, 0, rootAttrs.width - 1);
+    int y = std::clamp(screenPosition.y, 0, rootAttrs.height - 1);
+
+    // Install a temporary error handler so that if XGetImage still
+    // fails (e.g. on composited desktops) we don't crash.
+    static bool s_xerror = false;
+    s_xerror = false;
+    auto oldHandler = XSetErrorHandler([](::Display*, XErrorEvent*) -> int {
+      s_xerror = true;
+      return 0;
+    });
+
     XImage* image =
-      XGetImage(display, root, screenPosition.x, screenPosition.y, 1, 1, AllPlanes, ZPixmap);
-    if (image) {
-      XColor color;
-      color.pixel = XGetPixel(image, 0, 0);
-      XDestroyImage(image);
+      XGetImage(display, root, x, y, 1, 1, AllPlanes, ZPixmap);
 
-      XQueryColor(display, XDefaultColormap(display, screen), &color);
+    XSetErrorHandler(oldHandler);
 
-      // Each red/green/blue channel is 16-bit, so we have to convert to 8-bit.
-      return gfx::rgba(color.red >> 8, color.green >> 8, color.blue >> 8);
-    }
-    return gfx::ColorNone;
+    if (s_xerror || !image)
+      return gfx::ColorNone;
+
+    XColor color;
+    color.pixel = XGetPixel(image, 0, 0);
+    XDestroyImage(image);
+
+    XQueryColor(display, XDefaultColormap(display, screen), &color);
+
+    // Each red/green/blue channel is 16-bit, so we have to convert to 8-bit.
+    return gfx::rgba(color.red >> 8, color.green >> 8, color.blue >> 8);
   }
 
   ScreenRef primaryScreen() override