From 95f186f36451c3d5cebd30649df64c390c77b62d Mon Sep 17 00:00:00 2001
From: Junegunn Choi <junegunn.c@gmail.com>
Date: Sun, 22 Mar 2026 09:55:07 +0900
Subject: [PATCH] Fix preview scrollbar not rendered after toggle-preview

Fix #4732
---
 src/terminal.go      |  2 +-
 test/test_preview.rb | 16 ++++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/terminal.go b/src/terminal.go
index 94a02587..98544f1b 100644
--- a/src/terminal.go
+++ b/src/terminal.go
@@ -4630,7 +4630,7 @@ func (t *Terminal) renderPreviewScrollbar(yoff int, barLength int, barStart int)
 	w := t.pborder.Width()
 	xw := [2]int{t.pwindow.Left(), t.pwindow.Width()}
 	redraw := false
-	if len(t.previewer.bar) != height || t.previewer.xw != xw {
+	if len(t.previewer.bar) != height || t.previewer.xw != xw || t.previewed.version != t.previewer.version {
 		redraw = true
 		t.previewer.bar = make([]bool, height)
 		t.previewer.xw = xw
diff --git a/test/test_preview.rb b/test/test_preview.rb
index 25579553..ac8919db 100644
--- a/test/test_preview.rb
+++ b/test/test_preview.rb
@@ -623,4 +623,20 @@ class TestPreview < TestInteractive
       assert_equal(0, lines.count { |line| line.include?('│ h') })
     end
   end
+
+  def test_preview_toggle_should_redraw_scrollbar
+    tmux.send_keys %(seq 1 | #{FZF} --no-border --scrollbar --preview 'seq $((FZF_PREVIEW_LINES + 1))' --preview-border line --bind tab:toggle-preview --header foo --header-border --footer bar --footer-border), :Enter
+    tmux.until do |lines|
+      assert_equal 1, lines.match_count
+      assert_operator lines.count { |line| line.end_with?('│') }, :>, 2
+    end
+    tmux.send_keys :Tab
+    tmux.until do |lines|
+      assert_equal(2, lines.count { |line| line.end_with?('│') })
+    end
+    tmux.send_keys :Tab
+    tmux.until do |lines|
+      assert_operator lines.count { |line| line.end_with?('│') }, :>, 2
+    end
+  end
 end