Fix app icon in alt+tab view on Windows

CHANGELOG.md

@@ -39,6 +39,7 @@ Notable changes to the `alacritty_terminal` crate are documented in its
 - Config import changes not being live reloaded
 - Cursor color requests with default cursor colors
 - Fullwidth semantic escape characters
+- Windows app icon now displays properly in old alt+tab on Windows
 
 ## 0.13.2
 

alacritty/src/display/window.rs

@@ -30,7 +30,7 @@ use winit::dpi::{PhysicalPosition, PhysicalSize};
 use winit::event_loop::ActiveEventLoop;
 use winit::monitor::MonitorHandle;
 #[cfg(windows)]
-use winit::platform::windows::IconExtWindows;
+use winit::platform::windows::{IconExtWindows, WindowAttributesExtWindows};
 use winit::raw_window_handle::{HasWindowHandle, RawWindowHandle};
 use winit::window::{
     CursorIcon, Fullscreen, ImePurpose, Theme, UserAttentionType, Window as WinitWindow,
@@ -302,7 +302,8 @@ impl Window {
 
         WinitWindow::default_attributes()
             .with_decorations(window_config.decorations != Decorations::None)
-            .with_window_icon(icon.ok())
+            .with_window_icon(icon.as_ref().ok().cloned())
+            .with_taskbar_icon(icon.ok())
     }
 
     #[cfg(target_os = "macos")]