diff --git a/main.lua b/main.lua
index 3eed834..fe4b313 100644
--- a/main.lua
+++ b/main.lua
@@ -596,7 +596,7 @@ function Bookhoard:setupOPDS()
         if server.url and (
             server.url == opds_url
             or server.url == opds_base_url
-            or util.startswith(server.url, opds_base_url .. "?")
+            or server.url:sub(1, #opds_base_url + 1) == opds_base_url .. "?"
         ) then
             servers[i] = {
                 title = "Bookhoard",