input: Avoid painting unset gutter background

crates/ui/src/input/element.rs

@@ -2122,25 +2122,18 @@ impl Element for TextElement {
         if let Some(line_numbers) = prepaint.line_numbers.as_ref() {
             offset_y += invisible_top_padding;
 
-            // Gutter background: prefer the dedicated `editor.gutter.background`
-            // theme key, falling back to the editor background so existing
-            // themes render unchanged.
-            let gutter_bg = cx
-                .theme()
-                .highlight_theme
-                .style
-                .editor_gutter_background
-                .unwrap_or_else(|| cx.theme().editor_background());
-            window.paint_quad(fill(
-                Bounds {
-                    origin: input_bounds.origin,
-                    size: size(
-                        prepaint.last_layout.line_number_width - LINE_NUMBER_RIGHT_MARGIN,
-                        input_bounds.size.height + prepaint.ghost_lines_height,
-                    ),
-                },
-                gutter_bg,
-            ));
+            if let Some(gutter_bg) = cx.theme().highlight_theme.style.editor_gutter_background {
+                window.paint_quad(fill(
+                    Bounds {
+                        origin: input_bounds.origin,
+                        size: size(
+                            prepaint.last_layout.line_number_width - LINE_NUMBER_RIGHT_MARGIN,
+                            input_bounds.size.height + prepaint.ghost_lines_height,
+                        ),
+                    },
+                    gutter_bg,
+                ));
+            }
 
             // Each item is the normal lines.
             for (lines, &buffer_line) in line_numbers