Suppress IE/Edge additional white/blue colors for focused <select>

scss/_forms.scss

@@ -60,6 +60,16 @@ select.form-control {
   &:not([size]):not([multiple]) {
     height: $input-height;
   }
+
+  &:focus::-ms-value {
+    // Suppress the nested default white text on blue background highlight given to
+    // the selected option text when the (still closed) <select> receives focus
+    // in IE and (under certain conditions) Edge, as it looks bad and cannot be made to
+    // match the appearance of the native widget.
+    // See https://github.com/twbs/bootstrap/issues/19398.
+    color: $input-color;
+    background-color: $input-bg;
+  }
 }
 
 // Make file inputs better match text inputs by forcing them to new lines.