Support startup notify on Wayland/X11

Activate a window to indicate that we want initial focus when the
system uses startup notifications.

Fixes #6931.

CHANGELOG.md

@@ -21,6 +21,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - `Back`/`Forward` mouse buttons support in bindings
 - Copy global IPC options (`-w -1`) for new windows
 - Bindings to create and navigate tabs on macOS
+- Support startup notify protocol to raise initial window on Wayland/X11
 
 ### Changed
 

alacritty/src/display/window.rs

@@ -1,3 +1,8 @@
+#[cfg(not(any(target_os = "macos", windows)))]
+use winit::platform::startup_notify::{
+    self, EventLoopExtStartupNotify, WindowBuilderExtStartupNotify,
+};
+
 #[cfg(all(not(feature = "x11"), not(any(target_os = "macos", windows))))]
 use winit::platform::wayland::WindowBuilderExtWayland;
 
@@ -143,6 +148,17 @@ impl Window {
                 .with_position(PhysicalPosition::<i32>::from((position.x, position.y)));
         }
 
+        #[cfg(not(any(target_os = "macos", windows)))]
+        if let Some(token) = event_loop.read_token_from_env() {
+            log::debug!("Activating window with token: {token:?}");
+            window_builder = window_builder.with_activation_token(token);
+
+            // Remove the token from the env.
+            unsafe {
+                startup_notify::reset_activation_token_env();
+            }
+        }
+
         let window = window_builder
             .with_title(&identity.title)
             .with_theme(config.window.decorations_theme_variant)

extra/linux/Alacritty.desktop

@@ -9,6 +9,7 @@ Categories=System;TerminalEmulator;
 Name=Alacritty
 GenericName=Terminal
 Comment=A fast, cross-platform, OpenGL terminal emulator
+StartupNotify=true
 StartupWMClass=Alacritty
 Actions=New;