diff --git a/unpacked/jax/output/HTML-CSS/jax.js b/unpacked/jax/output/HTML-CSS/jax.js
index 74f64f906..08ff79a08 100644
--- a/unpacked/jax/output/HTML-CSS/jax.js
+++ b/unpacked/jax/output/HTML-CSS/jax.js
@@ -84,14 +84,14 @@
         this.div.style.fontStyle  = (font.style||"normal");
       }
       var W = this.getComparisonWidths(font.testString,font.noStyleChar);
-      var found = false;
+      var found = null;
       if (W) {
         this.div.style.fontFamily = "'"+font.family+"',"+this.comparisonFont[0];
         if (this.div.offsetWidth == W[0]) {
           this.div.style.fontFamily = "'"+font.family+"',"+this.comparisonFont[W[2]];
-          if (this.div.offsetWidth == W[1]) {found = true}
+          if (this.div.offsetWidth == W[1]) {found = false}
         }
-        if (!found && (this.div.offsetWidth != W[3] || this.div.offsetHeight != W[4])) {
+        if (found === null && (this.div.offsetWidth != W[3] || this.div.offsetHeight != W[4])) {
           if (!font.noStyleChar && HTMLCSS.FONTDATA && HTMLCSS.FONTDATA.hasStyleChar) {
             for (var i = 0, m = this.testSize.length; i < m; i++)
               {if (this.testStyleChar(font,this.testSize[i])) {found = true; m = 0}}