diff --git a/tasks/util/browserify_wrapper.js b/tasks/util/browserify_wrapper.js
index b0364a6682b..2b12ce28767 100644
--- a/tasks/util/browserify_wrapper.js
+++ b/tasks/util/browserify_wrapper.js
@@ -4,6 +4,7 @@ var path = require('path');
 var browserify = require('browserify');
 var minify = require('minify-stream');
 var derequire = require('derequire');
+var substr2slice = require('./substr2slice');
 var through = require('through2');
 
 var strictD3 = require('./strict_d3');
@@ -78,7 +79,7 @@ module.exports = function _bundle(pathToIndex, pathToBundle, opts, cb) {
         };
 
         bundleStream
-            .pipe(applyDerequire())
+            .pipe(modify())
             .pipe(minify(minifyOpts))
             .pipe(fs.createWriteStream(pathToMinBundle))
             .on('finish', function() {
@@ -89,7 +90,7 @@ module.exports = function _bundle(pathToIndex, pathToBundle, opts, cb) {
 
     if(pathToBundle) {
         bundleStream
-            .pipe(applyDerequire())
+            .pipe(modify())
             .pipe(fs.createWriteStream(pathToBundle))
             .on('finish', function() {
                 logger(pathToBundle);
@@ -103,13 +104,19 @@ function logger(pathToOutput) {
     console.log(log);
 }
 
-function applyDerequire() {
-    var buf = '';
+function modify() {
+    var str = '';
     return through(function(chunk, enc, next) {
-        buf += chunk.toString();
+        str += chunk.toString();
         next();
     }, function(done) {
-        this.push(derequire(buf));
+        this.push(
+            derequire( // require >> _dereq_
+                substr2slice( // substr >> slice
+                    str
+                )
+            )
+        );
         done();
     });
 }
diff --git a/tasks/util/substr2slice.js b/tasks/util/substr2slice.js
new file mode 100644
index 00000000000..2ac033d0060
--- /dev/null
+++ b/tasks/util/substr2slice.js
@@ -0,0 +1,65 @@
+'use strict';
+
+// Replace .substr(a, ?b) with .slice(a, (a)+b)
+//
+// String.prototype.substr() is deprecated!
+// See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/substr
+
+module.exports = function substr2slice(str) {
+    var i0 = 0;
+    while(i0 !== -1) {
+        // assuming there is no white space after substr
+        i0 = str.indexOf('.substr(', i0);
+        if(i0 === -1) return str;
+
+        var args = [];
+        var text = '';
+        var k = 0;
+
+        // step into the function
+        var i = i0 + 7;
+        var p = 1; // open parentheses
+        while(p > 0) {
+            i++;
+
+            var c = str.charAt(i);
+            if(!c) break;
+            if(p === 1 && (
+                c === ',' ||
+                c === ')'
+            )) {
+                args[k++] = text;
+                text = '';
+            } else {
+                text += c;
+            }
+
+            if(c === '(') p++;
+            if(c === ')') p--;
+        }
+
+        // console.log(str.slice(i0, i + 1));
+        // console.log(args);
+
+        var startStr = args[0];
+        var lengthStr = args[1];
+        var out = '.slice(' + startStr;
+
+        if(lengthStr !== undefined) {
+            out += ',';
+            if(+startStr !== 0) {
+                out += '(' + startStr + ') + ';
+            }
+            out += lengthStr;
+        }
+
+        out += ')';
+
+        // console.log(out)
+        // console.log('__');
+
+        str = str.slice(0, i0) + out + str.slice(i + 1);
+    }
+
+    return str;
+};
diff --git a/tasks/util/watchified_bundle.js b/tasks/util/watchified_bundle.js
index d9652bf2ce9..43dc2fa20ab 100644
--- a/tasks/util/watchified_bundle.js
+++ b/tasks/util/watchified_bundle.js
@@ -3,7 +3,9 @@ var fs = require('fs');
 var browserify = require('browserify');
 var watchify = require('watchify');
 var prettySize = require('prettysize');
+var through = require('through2');
 
+var substr2slice = require('../../tasks/util/substr2slice');
 var constants = require('./constants');
 var common = require('./common');
 
@@ -50,6 +52,7 @@ module.exports = function makeWatchifiedBundle(strict, onFirstBundleCallback) {
                 firstBundle = false;
             }
         })
+        .pipe(modify())
         .pipe(
             fs.createWriteStream(constants.pathToPlotlyBuild)
         );
@@ -81,3 +84,18 @@ function formatBundleMsg(b, bundleName) {
         console.log(msgParts.join(' '));
     });
 }
+
+function modify() {
+    var str = '';
+    return through(function(chunk, enc, next) {
+        str += chunk.toString();
+        next();
+    }, function(done) {
+        this.push(
+            substr2slice( // substr >> slice
+                str
+            )
+        );
+        done();
+    });
+}