diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/BindingsGenerator/IDLGenerators.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/BindingsGenerator/IDLGenerators.cpp
index 98cb8031a18..77fd065e818 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/BindingsGenerator/IDLGenerators.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/BindingsGenerator/IDLGenerators.cpp
@@ -1651,8 +1651,13 @@ static void generate_to_cpp(SourceGenerator& generator, ParameterType& parameter
                     } else if (optional_default_value->to_number<int>().has_value() || optional_default_value->to_number<unsigned>().has_value()) {
                         union_generator.append(R"~~~(
     @union_type@ @cpp_name@ = @js_name@@js_suffix@.is_undefined() ? @parameter.optional_default_value@ : TRY(@js_name@@js_suffix@_to_variant(@js_name@@js_suffix@));
+)~~~");
+                    } else if (optional_default_value == "true"sv || optional_default_value == "false"sv) {
+                        union_generator.append(R"~~~(
+    @union_type@ @cpp_name@ = @js_name@@js_suffix@.is_undefined() ? @parameter.optional_default_value@ : TRY(@js_name@@js_suffix@_to_variant(@js_name@@js_suffix@));
 )~~~");
                     } else {
+                        dbgln("Don't know how to handle optional default value of `{}`", *optional_default_value);
                         TODO();
                     }
                 }