From ebd306acc12e75a5666d3b7a8010daabdeefb26b Mon Sep 17 00:00:00 2001
From: sbjwin <sbjwin4271@gmail.com>
Date: Thu, 5 Nov 2026 12:51:29 +0900
Subject: [PATCH] UI: request repaint on stale thumbnail return to finish
 grayscale refresh

---
 crates/ui-egui/src/textures.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/crates/ui-egui/src/textures.rs b/crates/ui-egui/src/textures.rs
index f7accb8b3..d0f764066 100644
--- a/crates/ui-egui/src/textures.rs
+++ b/crates/ui-egui/src/textures.rs
@@ -394,7 +394,8 @@ impl Textures {
             return Some(e.tex.clone());
         }
         if *budget == 0 {
-            // Keep showing the stale thumbnail while the new one waits.
+            // Keep showing the stale thumbnail while the new one waits; request a repaint to finish rendering.
+            ctx.request_repaint();
             return self.thumbs.get(&key.slide).map(|e| e.tex.clone());
         }
         *budget -= 1;