diff --git a/R/step1_helper_facets.R b/R/step1_helper_facets.R
index d7a32ec8..6e5cc9f5 100644
--- a/R/step1_helper_facets.R
+++ b/R/step1_helper_facets.R
@@ -169,8 +169,7 @@ step1_rearrange_facets = function(tmo, o) {
 				popup.format = process_label_format(popup.format, o$label.format)
 				
 				if (!all(popup.vars %in% smeta$vars)) {
-					# TODO add a more informative message that says which variables are incorrect.
-					stop("Incorrrect popup.vars specification", call. = FALSE)
+					rlang::arg_match(popup.vars, values = smeta$vars, multiple = TRUE)
 				}
 				if (length(popup.vars)) add_used_vars(popup.vars)