diff --git a/dist/flexsearch.bundle.debug.js b/dist/flexsearch.bundle.debug.js
index 426c42c..6f514c8 100644
--- a/dist/flexsearch.bundle.debug.js
+++ b/dist/flexsearch.bundle.debug.js
@@ -5,7 +5,7 @@
  * Hosted by Nextapps GmbH
  * https://github.com/nextapps-de/flexsearch
  */
-(function _f(self){'use strict';try{if(module)self=module}catch(e){}self._factory=_f;
+(function _f(self){'use strict';if(typeof module!=='undefined')self=module;self._factory=_f;
 var u;
 function y(a, b, c) {
   const d = typeof c, e = typeof a;
diff --git a/dist/flexsearch.bundle.min.js b/dist/flexsearch.bundle.min.js
index 40bfcb2..a394354 100644
--- a/dist/flexsearch.bundle.min.js
+++ b/dist/flexsearch.bundle.min.js
@@ -5,7 +5,7 @@
  * Hosted by Nextapps GmbH
  * https://github.com/nextapps-de/flexsearch
  */
-(function _f(self){'use strict';try{if(module)self=module}catch(e){}self._factory=_f;var u;function y(a,b,c){const d=typeof c,e=typeof a;if("undefined"!==d){if("undefined"!==e){if(c){if("function"===e&&d===e)return function(h){return a(c(h))};b=a.constructor;if(b===c.constructor){if(b===Array)return c.concat(a);if(b===Map){var f=new Map(c);for(var g of a)f.set(g[0],g[1]);return f}if(b===Set){g=new Set(c);for(f of a.values())g.add(f);return g}}}return a}return c}return"undefined"===e?b:a}function z(){return Object.create(null)}function aa(a,b){return b.length-a.length}
+(function _f(self){'use strict';if(typeof module!=='undefined')self=module;self._factory=_f;var u;function y(a,b,c){const d=typeof c,e=typeof a;if("undefined"!==d){if("undefined"!==e){if(c){if("function"===e&&d===e)return function(h){return a(c(h))};b=a.constructor;if(b===c.constructor){if(b===Array)return c.concat(a);if(b===Map){var f=new Map(c);for(var g of a)f.set(g[0],g[1]);return f}if(b===Set){g=new Set(c);for(f of a.values())g.add(f);return g}}}return a}return c}return"undefined"===e?b:a}function z(){return Object.create(null)}function aa(a,b){return b.length-a.length}
 function B(a){return"string"===typeof a}function C(a){return"object"===typeof a}function ba(a){const b=[];for(const c of a.keys())b.push(c);return b}function ca(a,b){if(B(b))a=a[b];else for(let c=0;a&&c<b.length;c++)a=a[b[c]];return a}function da(a){let b=0;for(let c=0,d;c<a.length;c++)(d=a[c])&&b<d.length&&(b=d.length);return b};var ea=[["\u00aa","a"],["\u00b2","2"],["\u00b3","3"],["\u00b9","1"],["\u00ba","o"],["\u00bc","1\u20444"],["\u00bd","1\u20442"],["\u00be","3\u20444"],["\u00e0","a"],["\u00e1","a"],["\u00e2","a"],["\u00e3","a"],["\u00e4","a"],["\u00e5","a"],["\u00e7","c"],["\u00e8","e"],["\u00e9","e"],["\u00ea","e"],["\u00eb","e"],["\u00ec","i"],["\u00ed","i"],["\u00ee","i"],["\u00ef","i"],["\u00f1","n"],["\u00f2","o"],["\u00f3","o"],["\u00f4","o"],["\u00f5","o"],["\u00f6","o"],["\u00f9","u"],["\u00fa","u"],["\u00fb",
 "u"],["\u00fc","u"],["\u00fd","y"],["\u00ff","y"],["\u0101","a"],["\u0103","a"],["\u0105","a"],["\u0107","c"],["\u0109","c"],["\u010b","c"],["\u010d","c"],["\u010f","d"],["\u0113","e"],["\u0115","e"],["\u0117","e"],["\u0119","e"],["\u011b","e"],["\u011d","g"],["\u011f","g"],["\u0121","g"],["\u0123","g"],["\u0125","h"],["\u0129","i"],["\u012b","i"],["\u012d","i"],["\u012f","i"],["\u0133","ij"],["\u0135","j"],["\u0137","k"],["\u013a","l"],["\u013c","l"],["\u013e","l"],["\u0140","l"],["\u0144","n"],
 ["\u0146","n"],["\u0148","n"],["\u0149","n"],["\u014d","o"],["\u014f","o"],["\u0151","o"],["\u0155","r"],["\u0157","r"],["\u0159","r"],["\u015b","s"],["\u015d","s"],["\u015f","s"],["\u0161","s"],["\u0163","t"],["\u0165","t"],["\u0169","u"],["\u016b","u"],["\u016d","u"],["\u016f","u"],["\u0171","u"],["\u0173","u"],["\u0175","w"],["\u0177","y"],["\u017a","z"],["\u017c","z"],["\u017e","z"],["\u017f","s"],["\u01a1","o"],["\u01b0","u"],["\u01c6","dz"],["\u01c9","lj"],["\u01cc","nj"],["\u01ce","a"],["\u01d0",
diff --git a/task/build.js b/task/build.js
index 83c3846..596bf2c 100644
--- a/task/build.js
+++ b/task/build.js
@@ -361,7 +361,7 @@ else (async function(){
         build = build.replace(/\(([a-z])=([a-z]).config\)&&\(([a-z])=([a-z])\)/, "($1=$2.config)&&($3=await import($4))");
 
         if(release === "bundle"){
-            build = build.replace("(function(self){'use strict';", "(function _f(self){'use strict';try{if(module)self=module}catch(e){}self._factory=_f;");
+            build = build.replace("(function(self){'use strict';", "(function _f(self){'use strict';if(typeof module!=='undefined')self=module;self._factory=_f;");
         }
 
         // replace the eval wrapper