diff --git a/Form1.cs b/Form1.cs
index c6732e3..3a72ba3 100644
--- a/Form1.cs
+++ b/Form1.cs
@@ -100,7 +100,7 @@ private void applyButton_Click(object sender, EventArgs e) {
 			if(checkBox1.Checked)
 				SetKv(ref acf, "AutoUpdateBehavior", "1");
 
-			acf = Regex.Replace(acf, "(\"" + AppInfo.DEPOT_ID + "\".*?\"manifest\"\\s*?)\"[0-9]{19}\"", $"$1\"{textbox_manifest.Text}\"", RegexOptions.Singleline | RegexOptions.IgnoreCase);
+			acf = Regex.Replace(acf, "(\"" + AppInfo.DEPOT_ID + "\".*?\"manifest\"\\s*?)\"[0-9]{16,19}\"", $"$1\"{textbox_manifest.Text}\"", RegexOptions.Singleline | RegexOptions.IgnoreCase);
 
 			File.WriteAllText(p, acf);