diff --git a/.gitignore b/.gitignore
index 0199a212bd..0dd8e57e41 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,6 +9,7 @@ yarn.lock
 node_modules
 # editor files
 .idea
+.vscode
 # export dir for gh-pages
 /gh-pages
 # temp benchmark data
diff --git a/js/compiler.ts b/js/compiler.ts
index fa865de438..4ffef30fcf 100644
--- a/js/compiler.ts
+++ b/js/compiler.ts
@@ -162,6 +162,7 @@ class Compiler implements ts.LanguageServiceHost, ts.FormatDiagnosticsHost {
   // arguments
   private readonly _options: ts.CompilerOptions = {
     allowJs: true,
+    allowNonTsExtensions: true,
     checkJs: true,
     esModuleInterop: true,
     module: ts.ModuleKind.ESNext,
diff --git a/rollup.config.js b/rollup.config.js
index 30d03bd776..5bfab06d91 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -266,11 +266,12 @@ export default function makeConfig(commandOptions) {
             "createLanguageService",
             "formatDiagnostics",
             "formatDiagnosticsWithColorAndContext",
+            "version",
+            "Extension",
             "ModuleKind",
             "ScriptKind",
             "ScriptSnapshot",
-            "ScriptTarget",
-            "version"
+            "ScriptTarget"
           ]
         }
       }),
diff --git a/tests/023_no_ext_with_mime b/tests/023_no_ext_with_mime
new file mode 100644
index 0000000000..87951d835e
--- /dev/null
+++ b/tests/023_no_ext_with_mime
@@ -0,0 +1 @@
+console.log("HELLO");
diff --git a/tests/023_no_ext_with_mime.mime b/tests/023_no_ext_with_mime.mime
new file mode 100644
index 0000000000..d7482e1bc1
--- /dev/null
+++ b/tests/023_no_ext_with_mime.mime
@@ -0,0 +1 @@
+application/javascript
\ No newline at end of file
diff --git a/tests/023_no_ext_with_mime.out b/tests/023_no_ext_with_mime.out
new file mode 100644
index 0000000000..e427984d4a
--- /dev/null
+++ b/tests/023_no_ext_with_mime.out
@@ -0,0 +1 @@
+HELLO
diff --git a/tests/023_no_ext_with_mime.test b/tests/023_no_ext_with_mime.test
new file mode 100644
index 0000000000..4a830aab71
--- /dev/null
+++ b/tests/023_no_ext_with_mime.test
@@ -0,0 +1,2 @@
+args: tests/023_no_ext_with_mime --reload --recompile
+output: tests/023_no_ext_with_mime.out
diff --git a/tests/024_import_no_ext_with_mime.test b/tests/024_import_no_ext_with_mime.test
new file mode 100644
index 0000000000..03bb6df93f
--- /dev/null
+++ b/tests/024_import_no_ext_with_mime.test
@@ -0,0 +1,2 @@
+args: tests/024_import_no_ext_with_mime.ts --reload --recompile
+output: tests/024_import_no_ext_with_mime.ts.out
diff --git a/tests/024_import_no_ext_with_mime.ts b/tests/024_import_no_ext_with_mime.ts
new file mode 100644
index 0000000000..d5140de668
--- /dev/null
+++ b/tests/024_import_no_ext_with_mime.ts
@@ -0,0 +1 @@
+import "./023_no_ext_with_mime";
diff --git a/tests/024_import_no_ext_with_mime.ts.out b/tests/024_import_no_ext_with_mime.ts.out
new file mode 100644
index 0000000000..e427984d4a
--- /dev/null
+++ b/tests/024_import_no_ext_with_mime.ts.out
@@ -0,0 +1 @@
+HELLO