diff --git a/unpacked/extensions/CHTML-preview.js b/unpacked/extensions/CHTML-preview.js
index 7f008647b..86704ae9d 100644
--- a/unpacked/extensions/CHTML-preview.js
+++ b/unpacked/extensions/CHTML-preview.js
@@ -51,7 +51,7 @@
     Config: function () {
       HUB.Config({
         "HTML-CSS": this.config.Chunks,
-        SVG: this.config.Chunks,
+        SVG: this.config.Chunks
       });
       MathJax.Ajax.Styles({".MathJax_Preview .MJXc-math":{color:this.config.color}});
       var update, delay, style, done, saved;
diff --git a/unpacked/jax/output/HTML-CSS/jax.js b/unpacked/jax/output/HTML-CSS/jax.js
index 95a5c3839..45e9d4e62 100644
--- a/unpacked/jax/output/HTML-CSS/jax.js
+++ b/unpacked/jax/output/HTML-CSS/jax.js
@@ -2109,7 +2109,7 @@
           HTMLCSS.addElement(span,"span",{style:{"font-size":scale}},[text]);
           if (variant.bold)   {span.lastChild.style.fontWeight = "bold"}
           if (variant.italic) {span.lastChild.style.fontStyle = "italic"}
-          delete span.bbox;
+          span.bbox = null;
           var HD = HTMLCSS.getHD(span), W = HTMLCSS.getW(span);
           span.bbox = {h:HD.h, d:HD.d, w:W, lw:0, rw:W, exactW: true};
         } else {
@@ -2850,7 +2850,7 @@
         //    Add the width to the span (outside the MathJax class, so uses outer em size,
         //    which makes it work even when minimum font size is in effect).
         //
-        span.style.width = HTMLCSS.Em((Math.round(math.bbox.w*this.em)+.25)/HTMLCSS.outerEm);
+        span.style.width = HTMLCSS.Em(Math.max(0,Math.round(math.bbox.w*this.em)+.25)/HTMLCSS.outerEm);
         span.style.display = "inline-block";
 	//
 	//  Adjust bbox to match outer em-size