diff --git a/frontend/src/utils/string.ts b/frontend/src/utils/string.ts
index 3600b89b..d22f50d1 100644
--- a/frontend/src/utils/string.ts
+++ b/frontend/src/utils/string.ts
@@ -30,7 +30,7 @@ export const isRegexString = (str: any) => {
  * Ensures value is wrapped in slashes: /value/
  */
 export const formatWithSlashes = (value: string): string => {
-  if (!value) return "/";
+  if (!value || typeof value !== "string") return "//";
   if (!value.startsWith("/")) value = "/" + value;
   if (!value.endsWith("/")) value = value + "/";
 
@@ -40,12 +40,17 @@ export const formatWithSlashes = (value: string): string => {
 /**
  * Extracts the inner regex from /.../
  */
-export const extractRegexBody = (value: string | undefined): string => {
-  if (value && value.startsWith("/") && value.endsWith("/")) {
+export const extractRegexBody = (value: string | undefined): string => {
+  if (
+    value &&
+    typeof value === "string" &&
+    value.startsWith("/") &&
+    value.endsWith("/")
+  ) {
     return value.slice(1, -1);
   }
 
-  return '';
+  return "";
 };
 
 /**