diff --git a/src/client/LangSelector.ts b/src/client/LangSelector.ts
index cff2e079e..766a0ddeb 100644
--- a/src/client/LangSelector.ts
+++ b/src/client/LangSelector.ts
@@ -71,6 +71,7 @@ export class LangSelector extends LitElement {
     if (supported.has(lang)) return lang;
 
     const base = lang.slice(0, 2);
+    if (supported.has(base)) return base;
     const candidates = Array.from(supported).filter((key) =>
       key.startsWith(base),
     );