From 7354b94f737c9f589803b23714e7eddfb2f0fd69 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Fri, 2 May 2025 08:53:43 +0200
Subject: [PATCH] osc: restore configured alpha if OSC-11 has no alpha value

When parsing an OSC-11 without an alpha value (i.e. standard OSC-11,
not rxvt's extended variant), restore the alpha value from the
configuration, rather than keeping whatever the current alpha is.
---
 CHANGELOG.md |  3 +++
 osc.c        | 21 +++++++++++++--------
 2 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 533f601c..54ad3a25 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -95,6 +95,9 @@
 ### Changed
 
 * `cursor.color` moved to `colors.cursor`.
+* OSC-11 without an alpha value will now restore the configured
+  (i.e. from `foot.ini`) alpha, rather than keeping whatever the
+  current alpha value is, unchanged.
 
 
 ### Deprecated
diff --git a/osc.c b/osc.c
index 7e3e6376..78f335e1 100644
--- a/osc.c
+++ b/osc.c
@@ -1455,15 +1455,20 @@ osc_dispatch(struct terminal *term)
 
         case 11:
             term->colors.bg = color;
-            if (have_alpha) {
-                const bool changed = term->colors.alpha != alpha;
-                term->colors.alpha = alpha;
-
-                if (changed) {
-                    wayl_win_alpha_changed(term->window);
-                    term_font_subpixel_changed(term);
-                }
+            if (!have_alpha) {
+                alpha = term->colors.active_theme == COLOR_THEME1
+                    ? term->conf->colors.alpha
+                    : term->conf->colors2.alpha;
             }
+
+            const bool changed = term->colors.alpha != alpha;
+            term->colors.alpha = alpha;
+
+            if (changed) {
+                wayl_win_alpha_changed(term->window);
+                term_font_subpixel_changed(term);
+            }
+
             term_damage_color(term, COLOR_DEFAULT, 0);
             term_damage_margins(term);
             break;