Index: gc_core/js/lang_core/gc_engine.js
==================================================================
--- gc_core/js/lang_core/gc_engine.js
+++ gc_core/js/lang_core/gc_engine.js
@@ -321,11 +321,11 @@
 
     load: function (sContext="JavaScript", sPath="") {
         try {
             if (typeof(require) !== 'undefined') {
                 var spellchecker = require("resource://grammalecte/graphspell/spellchecker.js");
-                _oSpellChecker = new spellchecker.SpellChecker("${lang}", "", "${dic_filename}.json");
+                _oSpellChecker = new spellchecker.SpellChecker("${lang}", "", "${dic_main_filename_js}", "${dic_extended_filename_js}", "${dic_personal_filename_js}");
             } else {
                 _oSpellChecker = new SpellChecker("${lang}", sPath, "${dic_main_filename_js}", "${dic_extended_filename_js}", "${dic_personal_filename_js}");
             }
             _sAppContext = sContext;
             _dOptions = gc_options.getOptions(sContext).gl_shallowCopy();     // duplication necessary, to be able to reset to default

Index: gc_lang/fr/build.py
==================================================================
--- gc_lang/fr/build.py
+++ gc_lang/fr/build.py
@@ -77,11 +77,11 @@
     "create extension for Thunderbird"
     print("Building extension for Thunderbird")
     sExtensionName = dVars['tb_identifier'] + "-v" + dVars['version'] + '.xpi'
     spfZip = "_build/" + sExtensionName
     hZip = zipfile.ZipFile(spfZip, mode='w', compression=zipfile.ZIP_DEFLATED)
-    _copyGrammalecteJSPackageInZipFile(hZip, spLangPack, dVars['dic_filename']+".json")
+    _copyGrammalecteJSPackageInZipFile(hZip, spLangPack)
     for spf in ["LICENSE.txt", "LICENSE.fr.txt"]:
         hZip.write(spf)
     dVars = _createOptionsForThunderbird(dVars)
     helpers.addFolderToZipAndFileFile(hZip, "gc_lang/"+sLang+"/tb", "", dVars, True)
     spDict = "gc_lang/"+sLang+"/xpi/data/dictionaries"
@@ -108,16 +108,18 @@
     for sLang in dVars['dOptLabel'].keys():
         dVars['gc_options_labels_'+sLang] = "\n".join( [ "<!ENTITY option.label." + sOpt + ' "' + dVars['dOptLabel'][sLang][sOpt][0] + '">'  for sOpt in dVars['dOptLabel'][sLang] ] )
     return dVars
 
 
-def _copyGrammalecteJSPackageInZipFile (hZip, spLangPack, sDicName, sAddPath=""):
+def _copyGrammalecteJSPackageInZipFile (hZip, spLangPack, sAddPath=""):
     for sf in os.listdir("grammalecte-js"):
         if not os.path.isdir("grammalecte-js/"+sf):
             hZip.write("grammalecte-js/"+sf, sAddPath+"grammalecte-js/"+sf)
     for sf in os.listdir("grammalecte-js/graphspell"):
         if not os.path.isdir("grammalecte-js/graphspell/"+sf):
             hZip.write("grammalecte-js/graphspell/"+sf, sAddPath+"grammalecte-js/graphspell/"+sf)
-    hZip.write("grammalecte-js/graphspell/_dictionaries/"+sDicName, sAddPath+"grammalecte-js/graphspell/_dictionaries/"+sDicName)
+    for sf in os.listdir("grammalecte-js/graphspell/_dictionaries"):
+        if not os.path.isdir("grammalecte-js/graphspell/_dictionaries/"+sf):
+            hZip.write("grammalecte-js/graphspell/_dictionaries/"+sf, sAddPath+"grammalecte-js/graphspell/_dictionaries/"+sf)
     for sf in os.listdir(spLangPack):
         if not os.path.isdir(spLangPack+"/"+sf):
             hZip.write(spLangPack+"/"+sf, sAddPath+spLangPack+"/"+sf)

Index: gc_lang/fr/tb/worker/gce_worker.js
==================================================================
--- gc_lang/fr/tb/worker/gce_worker.js
+++ gc_lang/fr/tb/worker/gce_worker.js
@@ -49,11 +49,11 @@
 let tkz = null; // module: tokenizer
 let lxg = null; // module: lexicographer
 let helpers = null;
 
 let oTokenizer = null;
-let oDict = null;
+let oSpellChecker = null;
 let oLxg = null;
 
 function loadGrammarChecker (sGCOptions="", sContext="JavaScript") {
     if (gce === null) {
         try {
@@ -63,11 +63,11 @@
             tkz = require("resource://grammalecte/graphspell/tokenizer.js");
             //lxg = require("resource://grammalecte/fr/lexicographe.js");
             oTokenizer = new tkz.Tokenizer("fr");
             //helpers.setLogOutput(worker.log);
             gce.load(sContext);
-            oDict = gce.getDictionary();
+            oSpellChecker = gce.getSpellChecker();
             if (sGCOptions !== "") {
                 gce.setOptions(helpers.objectToMap(JSON.parse(sGCOptions)));
             }
             // we always retrieve options from the gce, for setOptions filters obsolete options
             return gce.getOptions().gl_toString();
@@ -83,11 +83,11 @@
     return JSON.stringify(aGrammErr);
 }
 
 function parseAndSpellcheck (sText, sCountry, bDebug, bContext) {
     let aGrammErr = gce.parse(sText, sCountry, bDebug, bContext);
-    let aSpellErr = oTokenizer.getSpellingErrors(sText, oDict);
+    let aSpellErr = oTokenizer.getSpellingErrors(sText, oSpellChecker);
     return JSON.stringify({ aGrammErr: aGrammErr, aSpellErr: aSpellErr });
 }
 
 function getOptions () {
     return gce.getOptions().gl_toString();
@@ -111,11 +111,11 @@
     gce.resetOptions();
     return gce.getOptions().gl_toString();
 }
 
 function fullTests (sGCOptions="") {
-    if (!gce || !oDict) {
+    if (!gce || !oSpellChecker) {
         return "# Error: grammar checker or dictionary not loaded."
     }
     let dMemoOptions = gce.getOptions();
     if (sGCOptions) {
         gce.setOptions(helpers.objectToMap(JSON.parse(sGCOptions)));

Index: graphspell-js/spellchecker.js
==================================================================
--- graphspell-js/spellchecker.js
+++ graphspell-js/spellchecker.js
@@ -25,24 +25,24 @@
 ]);
 
 
 class SpellChecker {
 
-    constructor (sLangCode, sPath="", mainDic=null, extentedDic=null, personalDic=null) {
+    constructor (sLangCode, sPath="", mainDic="", extentedDic="", personalDic="") {
         // returns true if the main dictionary is loaded
         this.sLangCode = sLangCode;
-        if (mainDic === null) {
+        if (!mainDic) {
             mainDic = dDefaultDictionaries.gl_get(sLangCode, "");
         }
         this.oMainDic = this._loadDictionary(mainDic, sPath, true);
         this.oExtendedDic = this._loadDictionary(extentedDic, sPath);
         this.oPersonalDic = this._loadDictionary(personalDic, sPath);
     }
 
     _loadDictionary (dictionary, sPath, bNecessary=false) {
         // returns an IBDAWG object
-        if (dictionary === null) {
+        if (!dictionary) {
             return null;
         }
         try {
             if (typeof(require) !== 'undefined') {
                 return new ibdawg.IBDAWG(dictionary);  // dictionary can be a filename or a JSON object
@@ -157,7 +157,7 @@
         }
     }
 }
 
 if (typeof(exports) !== 'undefined') {
-    exports.Spellchecker = Spellchecker;
+    exports.SpellChecker = SpellChecker;
 }