diff --git a/docs/_exts/bootstrap.py b/docs/_exts/bootstrap.py
index bb0e595c4d1..18e46cea160 100644
--- a/docs/_exts/bootstrap.py
+++ b/docs/_exts/bootstrap.py
@@ -96,7 +96,7 @@ class BootstrapHTML5TranslatorMixin:
         self.body.append(tag)
 
 def setup_translators(app):
-    if app.builder.default_translator_class is None:
+    if app.builder.format != "html":
         return
 
     if not app.registry.translators.items():
@@ -111,10 +111,6 @@ def setup_translators(app):
         app.set_translator(app.builder.name, translator, override=True)
     else:
         for name, klass in app.registry.translators.items():
-            if app.builder.format != "html":
-                # Skip translators that are not HTML
-                continue
-
             translator = types.new_class(
                 "BootstrapHTML5Translator",
                 (