diff --git a/.editorconfig b/.editorconfig
index 5407e16..1ebc6e5 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -13,3 +13,5 @@ indent_size = 4
 
 [*.md]
 trim_trailing_whitespace = false
+# The YAML frontmatter doesn't allow tabs.
+indent_style = space