diff --git a/desktop/tests/gui_base_test.py b/desktop/tests/gui_base_test.py
index 9fbb4309..2bf762e1 100644
--- a/desktop/tests/gui_base_test.py
+++ b/desktop/tests/gui_base_test.py
@@ -177,6 +177,13 @@ class GuiBaseTest(unittest.TestCase):
         tab.get_mode().toggle_history.click()
         self.assertEqual(tab.get_mode().history.isVisible(), not currently_visible)
 
+    def javascript_is_correct_mime_type(self, tab, file):
+        """Test that the javascript file send.js is fetchable and that its MIME type is correct"""
+        path = f"{tab.get_mode().web.static_url_path}/js/{file}"
+        url = f"http://127.0.0.1:{tab.app.port}/{path}"
+        r = requests.get(url)
+        self.assertTrue(r.headers["Content-Type"].startswith("text/javascript;"))
+
     def history_indicator(self, tab, indicator_count="1"):
         """Test that we can make sure the history is toggled off, do an action, and the indicator works"""
         # Make sure history is toggled off
diff --git a/desktop/tests/test_gui_chat.py b/desktop/tests/test_gui_chat.py
index 786782f7..ee6c0787 100644
--- a/desktop/tests/test_gui_chat.py
+++ b/desktop/tests/test_gui_chat.py
@@ -61,6 +61,7 @@ class TestChat(GuiBaseTest):
         tab = self.new_chat_tab()
         self.run_all_chat_mode_started_tests(tab)
         self.view_chat(tab)
+        self.javascript_is_correct_mime_type(tab, "chat.js")
         self.change_username(tab)
         self.run_all_chat_mode_stopping_tests(tab)
         self.close_all_tabs()
diff --git a/desktop/tests/test_gui_receive.py b/desktop/tests/test_gui_receive.py
index ca69c957..8c1c44b3 100644
--- a/desktop/tests/test_gui_receive.py
+++ b/desktop/tests/test_gui_receive.py
@@ -122,6 +122,7 @@ class TestReceive(GuiBaseTest):
     def run_all_receive_mode_tests(self, tab):
         """Submit files and messages in receive mode and stop the share"""
         self.run_all_receive_mode_setup_tests(tab)
+        self.javascript_is_correct_mime_type(tab, "receive.js")
         self.upload_file(tab, self.tmpfile_test, "test.txt")
         self.history_widgets_present(tab)
         self.counter_incremented(tab, 1)
diff --git a/desktop/tests/test_gui_share.py b/desktop/tests/test_gui_share.py
index 2cc48d17..ba175fa9 100644
--- a/desktop/tests/test_gui_share.py
+++ b/desktop/tests/test_gui_share.py
@@ -197,6 +197,7 @@ class TestShare(GuiBaseTest):
             self.tmpfile_test
         )
         self.web_page(tab, "Total size")
+        self.javascript_is_correct_mime_type(tab, "send.js")
         self.download_share(tab)
         self.history_widgets_present(tab)
         self.server_is_stopped(tab)