From 78c1f81bd54ea28bdb6bea58feceba93991e4b79 Mon Sep 17 00:00:00 2001
From: Igor Kolokolnikov <igor@kolokolnikov.dev>
Date: Tue, 29 Sep 2026 20:37:36 -0700
Subject: [PATCH] Remove window flicker on start by clearing the window with
 black after creation.

---
 slock.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/slock.c b/slock.c
index fdfd40d..b15eb55 100644
--- a/slock.c
+++ b/slock.c
@@ -999,6 +999,10 @@ lockscreen(Display *dpy, struct xrandr *rr, int screen)
                               DefaultVisual(dpy, lock->screen),
                               CWOverrideRedirect | CWBackPixel, &wa);
 #endif
+
+    XSetWindowBackground(dpy, lock->win, BlackPixel(dpy, screen));
+    XClearWindow(dpy, lock->win);
+
     lock->pmap = XCreateBitmapFromData(dpy, lock->win, curs, 8, 8);
     invisible = XCreatePixmapCursor(dpy, lock->pmap, lock->pmap,
                                     &color, &color, 0, 0);