diff --git a/helix-term/src/ui/completion.rs b/helix-term/src/ui/completion.rs
index fcd63199..a55201ff 100644
--- a/helix-term/src/ui/completion.rs
+++ b/helix-term/src/ui/completion.rs
@@ -328,8 +328,8 @@ impl Component for Completion {
                 let y = popup_y;
 
                 if let Some((rel_width, rel_height)) = markdown_doc.required_size((width, height)) {
-                    width = rel_width;
-                    height = rel_height;
+                    width = rel_width.min(width);
+                    height = rel_height.min(height);
                 }
                 Rect::new(x, y, width, height)
             } else {