diff --git a/lib/default_install_args.py b/lib/default_install_args.py
index 8d6f1e6..f975c42 100644
--- a/lib/default_install_args.py
+++ b/lib/default_install_args.py
@@ -4,7 +4,7 @@ import sys
 import json
 import toml
 
-def get_default_values_for_questions(manifest):
+def get_default_values_for_questions(manifest, raise_if_no_default=True):
 
     base_default_value_per_arg_type = {
         ("domain", "domain"): "domain.tld",
@@ -37,9 +37,10 @@ def get_default_values_for_questions(manifest):
                 choices = str(question["choices"])
             else:
                 choices = list(question["choices"].keys())
-            yield (name, question["choices"][0])
+            yield (name, choices[0])
         else:
-            raise Exception("No default value could be computed for arg " + name)
+            if raise_if_no_default:
+                raise Exception("No default value could be computed for arg " + name)
 
 if __name__ == '__main__':
     manifest_path = sys.argv[1:][0]
diff --git a/lib/parse_tests_toml.py b/lib/parse_tests_toml.py
index 8731363..f2911fa 100644
--- a/lib/parse_tests_toml.py
+++ b/lib/parse_tests_toml.py
@@ -136,7 +136,7 @@ def build_test_list(basedir):
     is_webapp = os.system(f"grep -q '^ynh_add_nginx_config' '{basedir}/scripts/install'") == 0
 
     from default_install_args import get_default_values_for_questions
-    default_install_args = {k: v for k, v in get_default_values_for_questions(manifest)}
+    default_install_args = {k: v for k, v in get_default_values_for_questions(manifest, raise_if_no_default=False)}
 
     base_test_list = list(generate_test_list_base(test_manifest, default_install_args, is_webapp, is_multi_instance))
     test_list = {test_suite_id: tests for test_suite_id, tests in filter_test_list(test_manifest, base_test_list)}