merge branch 'ie-stretchy-braces' into alpha

Author: dpvc

mathjax3-ts/output/chtml/Wrappers/mo.ts

@@ -80,17 +80,18 @@ export class CHTMLmo extends CHTMLWrapper {
         'mjx-stretchy-v': {
             display: 'inline-block'
         },
+        'mjx-stretchy-v > *': {
+            display: 'block'
+        },
         'mjx-stretchy-v > mjx-beg': {
-            display: 'block',
             height: 0
         },
-        'mjx-stretchy-v > mjx-end': {
-            display: 'block'
-        },
         'mjx-stretchy-v > mjx-end > mjx-c': {
             display: 'block'
         },
-        'mjx-stretchy-v > mjx-beg > mjx-c, mjx-stretchy-v > mjx-end > mjx-c': {
+        'mjx-stretchy-v > * > mjx-c': {
+            transform: 'scale(1)',   // improves Firefox positioning
+            'transform-origin': 'left center',
             overflow: 'hidden'
         },
         'mjx-stretchy-v > mjx-ext': {
@@ -101,7 +102,8 @@ export class CHTMLmo extends CHTMLWrapper {
             overflow: 'hidden'
         },
         'mjx-stretchy-v > mjx-ext > mjx-c': {
-            transform: 'scaleY(500) translateY(.1em)'
+            transform: 'scaleY(500) translateY(.1em)',
+            overflow: 'visible'
         },
         'mjx-mark': {
             display: 'inline-block',

mathjax3-ts/output/chtml/fonts/tex.ts

@@ -454,8 +454,9 @@ export class TeXFont extends FontData {
         const Hb = this.addDelimiterVPart(styles, c, 'beg', beg);
         this.addDelimiterVPart(styles, c, 'ext', ext);
         const He = this.addDelimiterVPart(styles, c, 'end', end);
+        let Hm;
         if (mid) {
-            this.addDelimiterVPart(styles, c, 'mid', mid);
+            Hm = this.addDelimiterVPart(styles, c, 'mid', mid);
             styles['.MJX-TEX mjx-stretchy-v[c="' + c + '"] > mjx-ext'] = {height: '50%'}
         }
         const css: StyleData = {};
@@ -464,10 +465,11 @@ export class TeXFont extends FontData {
         }
         if (He) {
             css['border-bottom-width'] = this.em0(He - .03);
-            css['margin-bottom'] = this.em(-He);
+            styles['.MJX-TEX mjx-stretchy-v[c="' + c + '"] > mjx-end'] = {'margin-top': this.em(-He)};
             if (mid) {
-                styles['.MJX-TEX mjx-stretchy-v[c="' + c + '"] > mjx-ext:last-of-type'] = {
-                    'margin-top': this.em(-He)
+                styles['.MJX-TEX mjx-stretchy-v[c="' + c + '"] > mjx-mid'] = {
+                    'margin-top': this.em(-Hm/2),
+                    'margin-bottom': this.em(-Hm/2)
                 };
             }
         }