diff --git a/src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Pages/Monitoring/Health.razor b/src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Pages/Monitoring/Health.razor
index b71bfda1..f237283f 100644
--- a/src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Pages/Monitoring/Health.razor
+++ b/src/ZB.MOM.WW.ScadaBridge.CentralUI/Components/Pages/Monitoring/Health.razor
@@ -89,10 +89,10 @@
                 <h6 class="text-muted mb-0 me-3">Site Health Trends</h6>
                 @if (_trendSiteKeys.Count > 0)
                 {
+                    @* OnTrendSiteChangedAsync is async — Blazor wraps it in an EventCallback so the returned Task IS awaited; keep the Async signature, do not change it to a void/fire-and-forget handler. This comment MUST stay OUTSIDE the <select> start tag: a Razor comment placed between attributes renders as an invalid attribute name and crashes the SignalR circuit (InvalidCharacterError on setAttribute). *@
                     <select class="form-select form-select-sm" style="width:auto"
                             data-test="site-health-trends-site"
                             value="@_trendSiteId"
-                            @* Blazor wraps this async handler in an EventCallback, so the returned Task IS awaited — keep the Async signature; do not change it to a void/fire-and-forget handler. *@
                             @onchange="OnTrendSiteChangedAsync">
                         @foreach (var key in _trendSiteKeys)
                         {