diff --git a/src/debugging/debugJS.js b/src/debugging/debugJS.js
index e58085d898de4c1bfd67c8c06f808772c8ab439e..7f1a9650c8aa8a80997420bc6d522bd6068ad8c4 100644
--- a/src/debugging/debugJS.js
+++ b/src/debugging/debugJS.js
@@ -75,7 +75,7 @@ window.findNaN = function findNan() {
 	var result = [];
 	for (var key in flatV) {
 		if (Number.isNaN(flatV[key])) {
-			result.push('$'+key);
+			result.push('$$'+key); /* double dollar signs to escape sugarcube markup */
 		}
 	}
 	return result;