diff --git a/pungi/checks.py b/pungi/checks.py
index 79fb9bc9..a38db3c3 100644
--- a/pungi/checks.py
+++ b/pungi/checks.py
@@ -516,7 +516,7 @@ def make_schema():
                 "required": ["url", "target", "git_branch"]
             },
 
-            "string_tuples": {
+            "string_pairs": {
                 "type": "array",
                 "items": {
                     "type": "array",
@@ -940,7 +940,7 @@ def make_schema():
             },
 
             "translate_paths": {
-                "$ref": "#/definitions/string_tuples",
+                "$ref": "#/definitions/string_pairs",
                 "default": [],
             },
 
@@ -1145,7 +1145,7 @@ def make_schema():
                                         "format": {
                                             "anyOf": [
                                                 # The variant with explicit extension is deprecated.
-                                                {"$ref": "#/definitions/string_tuples"},
+                                                {"$ref": "#/definitions/string_pairs"},
                                                 {"$ref": "#/definitions/strings"}
                                             ]
                                         },
diff --git a/pungi/phases/image_build.py b/pungi/phases/image_build.py
index cca9eeb4..22c60afe 100644
--- a/pungi/phases/image_build.py
+++ b/pungi/phases/image_build.py
@@ -136,7 +136,7 @@ class ImageBuildPhase(base.PhaseLoggerMixin, base.ImageConfigMixin, base.ConfigG
                 # just list of formats, or a single format.
                 formats = []
                 for format in force_list(image_conf["image-build"]["format"]):
-                    formats.append(format[0] if isinstance(format, tuple) else format)
+                    formats.append(format[0] if isinstance(format, (tuple, list)) else format)
                 image_conf["image-build"]["format"] = formats
                 image_conf["image-build"]['repo'] = self._get_repo(image_conf['image-build'], variant)