diff --git a/panflute/elements.py b/panflute/elements.py
index f875739..0c8881d 100644
--- a/panflute/elements.py
+++ b/panflute/elements.py
@@ -1248,6 +1248,7 @@ def _slots_to_json(self):
 
 RAW_FORMATS = {'tex',
                'latex',
+               'latex-merge',  # From Quarto output.
                'html',
                'context',
                'rtf',