From b5d9b7a32bb0835b45e34b1a12def2426acd1aac Mon Sep 17 00:00:00 2001
From: Chaosus <chaosus89@gmail.com>
Date: Tue, 2 Jun 2026 16:19:24 +0300
Subject: [PATCH] Properly update shader text syntax highlighting (for disabled
 regions)

---
 editor/shader/text_shader_editor.cpp |  1 +
 scene/gui/text_edit.cpp              | 13 +++++++++++--
 scene/gui/text_edit.h                |  1 +
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/editor/shader/text_shader_editor.cpp b/editor/shader/text_shader_editor.cpp
index 569da0ca5d..3f1916a175 100644
--- a/editor/shader/text_shader_editor.cpp
+++ b/editor/shader/text_shader_editor.cpp
@@ -1273,6 +1273,7 @@ void ShaderTextEditor::_validate_script() {
 			syntax_highlighter->add_disabled_branch_region(Point2i(region.from_line, region.to_line));
 		}
 	}
+	syntax_highlighter->emit_changed();
 
 	set_error("");
 	set_error_count(0);
diff --git a/scene/gui/text_edit.cpp b/scene/gui/text_edit.cpp
index a8c11414c0..cd092bd4ff 100644
--- a/scene/gui/text_edit.cpp
+++ b/scene/gui/text_edit.cpp
@@ -7029,12 +7029,16 @@ void TextEdit::set_syntax_highlighter(Ref<SyntaxHighlighter> p_syntax_highlighte
 		return;
 	}
 
+	if (syntax_highlighter.is_valid()) {
+		syntax_highlighter->disconnect_changed(callable_mp(this, &TextEdit::_syntax_highlighter_changed));
+	}
+
 	syntax_highlighter = p_syntax_highlighter;
 	if (syntax_highlighter.is_valid()) {
 		syntax_highlighter->set_text_edit(this);
+		syntax_highlighter->connect_changed(callable_mp(this, &TextEdit::_syntax_highlighter_changed));
 	}
-	_clear_syntax_highlighting_cache();
-	queue_redraw();
+	_syntax_highlighter_changed();
 }
 
 Ref<SyntaxHighlighter> TextEdit::get_syntax_highlighter() const {
@@ -9109,6 +9113,11 @@ void TextEdit::_clear_syntax_highlighting_cache() {
 	syntax_highlighting_cache.clear();
 }
 
+void TextEdit::_syntax_highlighter_changed() {
+	_clear_syntax_highlighting_cache();
+	queue_redraw();
+}
+
 /* Deprecated. */
 #ifndef DISABLE_DEPRECATED
 Vector<int> TextEdit::get_caret_index_edit_order() {
diff --git a/scene/gui/text_edit.h b/scene/gui/text_edit.h
index 6f3cd91799..8470cccd39 100644
--- a/scene/gui/text_edit.h
+++ b/scene/gui/text_edit.h
@@ -603,6 +603,7 @@ private:
 
 	Vector<Pair<int64_t, Color>> _get_line_syntax_highlighting(int p_line);
 	void _clear_syntax_highlighting_cache();
+	void _syntax_highlighter_changed();
 
 	/* Visual. */
 	struct ThemeCache {