diff --git a/extensions/callisto-theme.yaml b/extensions/callisto-theme.yaml
index e4ed986..b99478d 100644
--- a/extensions/callisto-theme.yaml
+++ b/extensions/callisto-theme.yaml
@@ -1,3 +1,4 @@
+---
 id: io.github.Lissy93.sn-callisto-theme
 github: Lissy93/callisto-theme-standard-notes
 main: dist/dist.css