diff --git a/tasks/preprocess.js b/tasks/preprocess.js
index 302628090ec..8753e7c160b 100644
--- a/tasks/preprocess.js
+++ b/tasks/preprocess.js
@@ -16,25 +16,32 @@ updateVersion(constants.pathToPlotlyVersion);
 
 // convert scss to css to js and static css file
 function makeBuildCSS() {
-    sass.render({
-        file: constants.pathToSCSS,
-        outputStyle: 'compressed'
-    }, function(err, result) {
-        if(err) throw err;
+    sass.render(
+        {
+            file: constants.pathToSCSS,
+            outputStyle: 'compressed'
+        },
+        function (err, result) {
+            if (err) throw err;
 
-        // To support application with strict CSP where styles cannot be inlined,
-        // build a static CSS file that can be included into such applications.
-        var staticCSS = String(result.css);
-        for(var k in mapBoxGLStyleRules) {
-            staticCSS = addAdditionalCSSRules(staticCSS, '.js-plotly-plot .plotly .mapboxgl-' + k, mapBoxGLStyleRules[k]);
-        }
-        fs.writeFile(constants.pathToCSSDist, staticCSS, function(err) {
-            if(err) throw err;
-        });
+            // To support application with strict CSP where styles cannot be inlined,
+            // build a static CSS file that can be included into such applications.
+            var staticCSS = String(result.css);
+            for (var k in mapBoxGLStyleRules) {
+                staticCSS = addAdditionalCSSRules(
+                    staticCSS,
+                    '.js-plotly-plot .plotly .mapboxgl-' + k,
+                    mapBoxGLStyleRules[k]
+                );
+            }
+            fs.writeFile(constants.pathToCSSDist, staticCSS, function (err) {
+                if (err) throw err;
+            });
 
-        // css to js to be inlined
-        pullCSS(String(result.css), constants.pathToCSSBuild);
-    });
+            // css to js to be inlined
+            pullCSS(String(result.css), constants.pathToCSSBuild);
+        }
+    );
 }
 
 function addAdditionalCSSRules(staticStyleString, selector, style) {
@@ -44,7 +51,7 @@ function addAdditionalCSSRules(staticStyleString, selector, style) {
 function exposePartsInLib() {
     var obj = {};
 
-    var insert = function(name, folder) {
+    var insert = function (name, folder) {
         obj[name] = folder + '/' + name;
     };
 
@@ -52,7 +59,7 @@ function exposePartsInLib() {
 
     insert('calendars', 'src/components');
 
-    constants.allTraces.forEach(function(k) {
+    constants.allTraces.forEach(function (k) {
         insert(k, 'src/traces');
     });
 
@@ -60,24 +67,23 @@ function exposePartsInLib() {
 }
 
 function writeLibFiles(obj) {
-    for(var name in obj) {
+    for (var name in obj) {
         common.writeFile(
             path.join(constants.pathToLib, name + '.js'),
-            [
-                '\'use strict\';',
-                '',
-                'module.exports = require(\'../' + obj[name] + '\');',
-                ''
-            ].join('\n')
+            ["'use strict';", '', "module.exports = require('../" + obj[name] + "');", ''].join('\n')
         );
     }
 }
 
 function copyTopojsonFiles() {
+    const FILES_TO_EXCLUDE = ['country_names_iso_codes.json'];
     fs.copy(
         constants.pathToTopojsonSrc,
         constants.pathToTopojsonDist,
-        { clobber: true },
+        {
+            clobber: true,
+            filter: (filePath) => !FILES_TO_EXCLUDE.includes(path.basename(filePath))
+        },
         common.throwOnError
     );
 }