diff --git a/www/code/export.js b/www/code/export.js
index 23d689361..04616a192 100644
--- a/www/code/export.js
+++ b/www/code/export.js
@@ -8,7 +8,7 @@ define([
     module.main = function (userDoc, cb) {
         var mode = userDoc.highlightMode || 'gfm';
         var content = userDoc.content;
-        module.type = SFCodeMirror.getContentExtension(mode);
+        module.ext = SFCodeMirror.getContentExtension(mode);
         cb(SFCodeMirror.fileExporter(content));
     };
 
diff --git a/www/common/modes.js b/www/common/modes.js
index ffed08b17..6d005da30 100644
--- a/www/common/modes.js
+++ b/www/common/modes.js
@@ -6,141 +6,141 @@ define([
     // mode language (extension)
     var list = Modes.list = [
         "APL apl .apl",
-        "ASCII-Armor asciiarmor",
-        "ASN.1 asn.1",
+        "ASCII-Armor asciiarmor .asc",
+        "ASN.1 asn.1 .asn1",
         "Asterisk asterisk",
         "Brainfuck brainfuck .b",
         "C text/x-csrc .c",
         "C text/x-c++src .cpp",
-        "C-like clike",
-        "Clojure clojure",
-        "CMake cmake",
-        "COBOL cobol",
-        "CoffeeScript coffeescript",
-        "Common_Lisp commonlisp",
-        "Crystal crystal",
+        "C-like clike .c",
+        "Clojure clojure .clj",
+        "CMake cmake _", /* no extension */
+        "COBOL cobol .cbl",
+        "CoffeeScript coffeescript .coffee",
+        "Common_Lisp commonlisp .lisp",
+        "Crystal crystal .cr",
         "CSS css .css",
-        "Cypher cypher",
-        "D d",
-        "Dart dart",
-        "Diff diff",
-        "Django django",
-        "Dockerfile dockerfile",
-        "DTD dtd",
-        "Dylan dylan",
-        "EBNF ebnf",
-        "ECL ecl",
-        "Eiffel eiffel",
+        "Cypher cypher .cypher",
+        "D d .d",
+        "Dart dart .dart",
+        "Diff diff .diff",
+        "Django django .py",
+        "Dockerfile dockerfile _", /* no extension */
+        "DTD dtd .dtd",
+        "Dylan dylan .dylan",
+        "EBNF ebnf .ebnf",
+        "ECL ecl .ecl",
+        "Eiffel eiffel .e",
         "Elm elm .elm",
-        "Erlang erlang",
-        "Factor factor",
-        "FCL fcl",
-        "Forth forth",
-        "Fortran fortran",
-        "GAS gas",
-        "Gherkin gherkin",
-        "Go go",
-        "Groovy groovy",
-        "Haml haml",
-        "Handlebars handlebars",
+        "Erlang erlang .erl",
+        "Factor factor .factor",
+        "FCL fcl .fcl",
+        "Forth forth .fs",
+        "Fortran fortran .f90",
+        "GAS gas .gas",
+        "Gherkin gherkin .feature",
+        "Go go .go",
+        "Groovy groovy .groovy",
+        "Haml haml .haml",
+        "Handlebars handlebars .hbs",
         "Haskell haskell .hs",
-        "Haskell-Literate haskell-literate",
-        "Haxe haxe",
+        "Haskell-Literate haskell-literate .lhs",
+        "Haxe haxe .hx",
         "HTML htmlmixed .html",
-        "HTTP http",
-        "IDL idl",
-        "JADE jade",
+        "HTTP http _", /* no extension */
+        "IDL idl .idl",
+        "JADE jade .jade",
         "Java text/x-java .java",
         "JavaScript javascript .js",
-        "Jinja2 jinja2",
+        "Jinja2 jinja2 .j2",
         "JSX jsx .jsx",
-        "Julia julia",
-        "LiveScript livescript",
-        "Lua lua",
+        "Julia julia .jl",
+        "LiveScript livescript .ls",
+        "Lua lua .lua",
         "Markdown gfm .md",
         //"markdown markdown .md",
-        "Mathematica mathematica",
-        "mIRC mirc",
-        "ML mllike",
-        "Modelica modelica",
-        "MscGen mscgen",
-        "MUMPS mumps",
-        "Nginx nginx",
-        "NSIS nsis",
-        "N-Triples ntriples",
+        "Mathematica mathematica .nb",
+        "mIRC mirc .irc",
+        "ML mllike _", /* no extension */
+        "Modelica modelica .mo",
+        "MscGen mscgen .mscgen",
+        "MUMPS mumps .m",
+        "Nginx nginx .conf",
+        "NSIS nsis .nsi",
+        "N-Triples ntriples .nq",
         "Objective-C text/x-objectivec .m",
-        "Octave octave",
+        "Octave octave .m",
         "Org-mode orgmode .org",
-        "Oz oz",
-        "Pascal pascal",
-        "PEG.js pegjs",
-        "Perl perl",
-        "PHP php",
-        "Pig pig",
-        "PowerShell powershell",
-        "Properties properties",
-        "Protocol_Buffers protobuf",
-        "Puppet puppet",
+        "Oz oz .oz",
+        "Pascal pascal .pas",
+        "PEG.js pegjs .pegjs",
+        "Perl perl .pl",
+        "PHP php .php",
+        "Pig pig .pig",
+        "PowerShell powershell .ps1",
+        "Properties properties .properties",
+        "Protocol_Buffers protobuf .proto",
+        "Puppet puppet .pp",
         "Python python .py",
-        "Q q",
-        "R r",
-        "RPM rpm",
-        "RST rst",
-        "Ruby ruby",
-        "Rust rust",
-        "Sass sass",
+        "Q q .q",
+        "R r .r",
+        "RPM rpm .rpm",
+        "RST rst .rst",
+        "Ruby ruby .rb",
+        "Rust rust .rs",
+        "Sass sass .sass",
         "Scheme scheme .scm",
         "Shell shell .sh",
-        "Sieve sieve",
-        "Slim slim",
-        "Smalltalk smalltalk",
-        "Smarty smarty",
-        "Solr solr",
-        "Soy soy",
-        "SPARQL sparql",
-        "Spreadsheet spreadsheet",
-        "SQL sql",
-        "sTeX stex",
-        "Stylus stylus",
-        "Swift swift",
-        "Tcl tcl",
+        "Sieve sieve .sieve",
+        "Slim slim .slim",
+        "Smalltalk smalltalk _", /* no extension */
+        "Smarty smarty _", /* no extension */
+        "Solr solr _", /* no extension */
+        "Soy soy .soy",
+        "SPARQL sparql .rq",
+        "Spreadsheet spreadsheet .xls",
+        "SQL sql .sql",
+        "sTeX stex .stex",
+        "Stylus stylus .styl",
+        "Swift swift .swift",
+        "Tcl tcl .tcl",
         "Text text .txt",
-        "Textile textile",
-        "TiddlyWiki tiddlywiki",
-        "Tiki tiki",
-        "TOML toml",
-        "Tornado tornado",
-        "troff troff",
+        "Textile textile .textile",
+        "TiddlyWiki tiddlywiki .tw",
+        "Tiki tiki _", /* no extension */
+        "TOML toml .toml",
+        "Tornado tornado .tornado",
+        "troff troff .troff",
         "TTCN ttcn",
         "TTCN-cfg ttcn-cfg",
-        "Turtle turtle",
-        "Twig twig",
-        "Visual_Basic vb",
-        "VBScript vbscript",
-        "Velocity velocity",
-        "Verilog verilog",
-        "VHDL vhdl",
-        "Vue vue",
-        "XML xml",
+        "Turtle turtle .ttl",
+        "Twig twig .twig",
+        "Visual_Basic vb .vb",
+        "VBScript vbscript .vbs",
+        "Velocity velocity .vm",
+        "Verilog verilog .v",
+        "VHDL vhdl .vhdl",
+        "Vue vue .vue",
+        "XML xml .xml",
         //"xwiki xwiki21",
-        "XQuery xquery",
+        "XQuery xquery .xquery",
         "YAML yaml .yaml",
-        "YAML_Frontmatter yaml-frontmatter",
-        "Z80 z80"
+        "YAML_Frontmatter yaml-frontmatter _", /* no extension */
+        "Z80 z80 .z80"
     ].map(function (line) {
         var kv = line.split(/\s/);
         return {
             language: kv[0].replace(/_/g, ' '),
             mode: kv[1],
-            ext: kv[2],
+            ext: kv[2] === '_' ? '' : kv[2],
         };
     });
 
     Modes.extensionOf = function (mode) {
-        var ext = '';
+        var ext;
         list.some(function (o) {
             if (o.mode !== mode) { return; }
-            ext = o.ext || '';
+            ext = o.ext;
             return true;
         });
         return ext;
diff --git a/www/common/sframe-app-framework.js b/www/common/sframe-app-framework.js
index af856d1d7..e2a0bd0a2 100644
--- a/www/common/sframe-app-framework.js
+++ b/www/common/sframe-app-framework.js
@@ -401,7 +401,7 @@ define([
                 var ext = (typeof(extension) === 'function') ? extension() : extension;
                 var suggestion = title.suggestTitle('cryptpad-document');
                 UI.prompt(Messages.exportPrompt,
-                    Util.fixFileName(suggestion) + '.' + ext, function (filename)
+                    Util.fixFileName(suggestion) + ext, function (filename)
                 {
                     if (!(typeof(filename) === 'string' && filename)) { return; }
                     if (async) {
@@ -454,7 +454,7 @@ define([
                         return;
                     }
                     if (!mediaTagEmbedder) { console.log('mediaTagEmbedder missing'); return; }
-                    if (data.type !== 'file') { console.log('unhandled embed type ' + data.type); return; } 
+                    if (data.type !== 'file') { console.log('unhandled embed type ' + data.type); return; }
                     var privateDat = cpNfInner.metadataMgr.getPrivateData();
                     var origin = privateDat.fileHost || privateDat.origin;
                     var src = data.src = origin + data.src;
diff --git a/www/common/sframe-common-codemirror.js b/www/common/sframe-common-codemirror.js
index bd35c298c..5c71bbee2 100644
--- a/www/common/sframe-common-codemirror.js
+++ b/www/common/sframe-common-codemirror.js
@@ -39,7 +39,8 @@ define([
     };
 
     module.getContentExtension = function (mode) {
-        return (Modes.extensionOf(mode) || '.txt').slice(1);
+        var ext = Modes.extensionOf(mode);
+        return ext !== undefined ? ext : '.txt';
     };
     module.fileExporter = function (content) {
         return new Blob([ content ], { type: 'text/plain;charset=utf-8' });
diff --git a/www/kanban/export.js b/www/kanban/export.js
index 2240031fe..9ee770ac7 100644
--- a/www/kanban/export.js
+++ b/www/kanban/export.js
@@ -2,7 +2,9 @@
 // Pads from the code app will be exported using this format instead of plain text.
 define([
 ], function () {
-    var module = {};
+    var module = {
+        ext: '.json'
+    };
 
     module.main = function (userDoc, cb) {
         var content = userDoc.content;
diff --git a/www/kanban/inner.js b/www/kanban/inner.js
index 29a4d9c88..609e5ac31 100644
--- a/www/kanban/inner.js
+++ b/www/kanban/inner.js
@@ -367,7 +367,7 @@ define([
             });
         }
 
-        framework.setFileExporter('json', function () {
+        framework.setFileExporter('.json', function () {
             return new Blob([JSON.stringify(kanban.getBoardsJSON(), 0, 2)], {
                 type: 'application/json',
             });
diff --git a/www/pad/export.js b/www/pad/export.js
index 263593a54..d1deef146 100644
--- a/www/pad/export.js
+++ b/www/pad/export.js
@@ -5,7 +5,7 @@ define([
     '/bower_components/nthen/index.js',
 ], function ($, Util, Hyperjson, nThen) {
     var module = {
-        type: 'html'
+        ext: '.html'
     };
 
     var exportMediaTags = function (inner, cb) {
diff --git a/www/pad/inner.js b/www/pad/inner.js
index 9b56e56bb..f201b8720 100644
--- a/www/pad/inner.js
+++ b/www/pad/inner.js
@@ -786,7 +786,7 @@ define([
             });
         }, true);
 
-        framework.setFileExporter(Exporter.type, function (cb) {
+        framework.setFileExporter(Exporter.ext, function (cb) {
             Exporter.main(inner, cb);
         }, true);
 
diff --git a/www/poll/export.js b/www/poll/export.js
index 2b915cced..e080ec9b4 100644
--- a/www/poll/export.js
+++ b/www/poll/export.js
@@ -3,7 +3,9 @@
 define([
     '/customize/messages.js',
 ], function (Messages) {
-    var module = {};
+    var module = {
+        ext: '.csv'
+    };
 
     var copyObject = function (obj) {
         return JSON.parse(JSON.stringify(obj));
diff --git a/www/settings/make-backup.js b/www/settings/make-backup.js
index 3e2876598..b86f1f3b2 100644
--- a/www/settings/make-backup.js
+++ b/www/settings/make-backup.js
@@ -34,7 +34,7 @@ define([
         var path = '/' + type + '/export.js';
         require([path], function (Exporter) {
             Exporter.main(json, function (data) {
-                result.ext = '.' + Exporter.type;
+                result.ext = Exporter.ext || '';
                 result.data = data;
                 cb(result);
             });
@@ -163,12 +163,12 @@ define([
         var existingNames = [];
         Object.keys(root).forEach(function (k) {
             var el = root[k];
-            if (typeof el === "object") {
+            if (typeof el === "object" && el.metadata !== true) { // if folder
                 var fName = getUnique(sanitize(k), '', existingNames);
                 existingNames.push(fName.toLowerCase());
                 return void makeFolder(ctx, el, zip.folder(fName), fd);
             }
-            if (ctx.data.sharedFolders[el]) {
+            if (ctx.data.sharedFolders[el]) { // if shared folder
                 var sfData = ctx.sf[el].metadata;
                 var sfName = getUnique(sanitize(sfData.title || 'Folder'), '', existingNames);
                 existingNames.push(sfName.toLowerCase());
diff --git a/www/slide/export.js b/www/slide/export.js
index 814950306..4e76f041d 100644
--- a/www/slide/export.js
+++ b/www/slide/export.js
@@ -4,7 +4,7 @@ define([
     '/common/sframe-common-codemirror.js',
 ], function (SFCodeMirror) {
     var module = {
-        type: 'md'
+        ext: '.md'
     };
 
     module.main = function (userDoc, cb) {
diff --git a/www/slide/inner.js b/www/slide/inner.js
index 1be2e5f3b..b5171d94f 100644
--- a/www/slide/inner.js
+++ b/www/slide/inner.js
@@ -538,7 +538,7 @@ define([
 
         editor.on('change', framework.localChange);
 
-        framework.setFileExporter(CodeMirror.getContentExtension, CodeMirror.fileExporter);
+        framework.setFileExporter(".md", CodeMirror.fileExporter);
         framework.setFileImporter({}, CodeMirror.fileImporter);
 
         framework.start();
diff --git a/www/whiteboard/export.js b/www/whiteboard/export.js
index e9f68e311..d3ea70f37 100644
--- a/www/whiteboard/export.js
+++ b/www/whiteboard/export.js
@@ -14,7 +14,7 @@ define([
         var canvas = new Fabric.Canvas(canvas_node);
         var content = userDoc.content;
         canvas.loadFromJSON(content, function () {
-            module.type = 'svg';
+            module.ext = '.svg';
             cb(canvas.toSVG());
         });
     };
diff --git a/www/whiteboard/inner.js b/www/whiteboard/inner.js
index 18a66a635..b0b382314 100644
--- a/www/whiteboard/inner.js
+++ b/www/whiteboard/inner.js
@@ -415,11 +415,11 @@ define([
             setEditable(!locked);
         });
 
-        framework.setFileExporter('png', function (cb) {
+        framework.setFileExporter('.png', function (cb) {
             $canvas[0].toBlob(function (blob) {
                 cb(blob);
             });
-        });
+        }, true);
 
         framework.setNormalizer(function (c) {
             return {