diff --git a/css/css.c b/css/css.c
index ffae4db38..b03f2342b 100644
--- a/css/css.c
+++ b/css/css.c
@@ -129,6 +129,7 @@ nserror nscss_create_css_data(struct content_css_data *c,
 	else
 		c->charset = NULL;
 
+	params.params_version = CSS_STYLESHEET_PARAMS_VERSION_1;
 	params.level = CSS_LEVEL_DEFAULT;
 	params.charset = charset;
 	params.url = url;
@@ -595,6 +596,7 @@ css_error nscss_register_import(struct content_css_data *c,
 		if (blank_import == NULL) {
 			css_stylesheet_params params;
 
+			params.params_version = CSS_STYLESHEET_PARAMS_VERSION_1;
 			params.level = CSS_LEVEL_DEFAULT;
 			params.charset = NULL;
 			params.url = "";
diff --git a/css/select.c b/css/select.c
index e9a75cfe5..d4d6361b7 100644
--- a/css/select.c
+++ b/css/select.c
@@ -110,6 +110,8 @@ static uint8_t charToHex(char c);
  * Selection callback table for libcss
  */
 static css_select_handler selection_handler = {
+	CSS_SELECT_HANDLER_VERSION_1,
+
 	node_name,
 	node_classes,
 	node_id,
@@ -167,6 +169,7 @@ css_stylesheet *nscss_create_inline_style(const uint8_t *data, size_t len,
 	css_stylesheet *sheet;
 	css_error error;
 
+	params.params_version = CSS_STYLESHEET_PARAMS_VERSION_1;
 	params.level = CSS_LEVEL_DEFAULT;
 	params.charset = charset;
 	params.url = url;