diff --git a/packages/coding-agent/src/core/settings-manager.ts b/packages/coding-agent/src/core/settings-manager.ts
index 1d13dbe4..c82ef528 100644
--- a/packages/coding-agent/src/core/settings-manager.ts
+++ b/packages/coding-agent/src/core/settings-manager.ts
@@ -680,6 +680,7 @@ export class SettingsManager {
 
 	setAutocompleteMaxVisible(maxVisible: number): void {
 		this.globalSettings.autocompleteMaxVisible = Math.max(3, Math.min(20, Math.floor(maxVisible)));
+		this.markModified("autocompleteMaxVisible");
 		this.save();
 	}