configure_window(ABOVE) after map_window prevents focus on Cinnamon X11

Description

On Cinnamon's window manager (Muffin), winit windows do not receive focus when mapped. This affects all winit-based applications on Cinnamon X11 (e.g. alacritty — see alacritty/alacritty#8832).

Root Cause

When mapping a window, winit calls configure_window(stack_mode: ABOVE) immediately after map_window, both in set_visible(true) and during initial window creation:

https://github.com/rust-windowing/winit/blob/v0.30.12/src/platform_impl/linux/x11/window.rs#L1137-L1145

self.xconn.xcb_connection().map_window(self.xwindow)...;
self.xconn.xcb_connection().configure_window(
    self.xwindow,
    &xproto::ConfigureWindowAux::new().stack_mode(xproto::StackMode::ABOVE),
)...;

This mimics XMapRaised. Muffin interprets the configure_window(ABOVE) as a focus-steal attempt and suppresses focus for the window.

Verification

Minimal reproduction with raw Xlib calls confirms the issue:

• XMapWindow alone → window receives focus ✓
• XMapWindow + XConfigureWindow(CWStackMode, Above) → window does not receive focus ✗

Building alacritty against a patched winit with the configure_window(ABOVE) removed from set_visible fixes the issue completely.

Suggested Fix

Remove the configure_window(ABOVE) call after map_window. It is redundant for new windows — newly mapped windows already appear at the top of the stack by default per ICCCM. The same code path exists in both set_visible(true) (line 1139) and initial window creation (line 510).

Related

This is a continuation of #1160 / #1176, which removed an XSetInputFocus call that was also causing focus-stealing. The configure_window(ABOVE) was left in place at the time.

Environment

• Cinnamon 6.6.6 (Muffin window manager)
• Linux Mint 22.3 / X11
• winit 0.30.12

Start in src/platform_impl/linux/x11/window.rs at the window-creation code around line 510 and set_visible(true) around line 1139. Compare the map_window and configure_window(ABOVE) calls with the reported raw Xlib reproduction. Done means the redundant ABOVE configuration is removed from both paths and Cinnamon X11 windows receive focus when mapped.