add inline note about navbar sizing

components.html

@@ -2174,7 +2174,7 @@ base_url: "../"
 
     <h2 id="navbar-forms">Forms</h2>
     <p>Place form content within <code>.navbar-form</code> for proper vertical alignment and collapsed behavior in narrow viewports. Use the alignment options to decide where it resides within the navbar content.</p>
-    <p>As a heads up, <code>.navbar-form</code> shares much of its code with <code>.form-inline</code> via mixin.</p>
+    <p>As a heads up, <code>.navbar-form</code> shares much of its code with <code>.form-inline</code> via mixin. <strong class="text-danger">Some form controls, like input groups, may require fixed widths to be show up properly within a navbar.</strong></p>
     <div class="bs-example">
       <nav class="navbar navbar-default" role="navigation">
         <div class="navbar-header">