Crbug/1173575, non-JS module files deprecated. chromewebdata/(index)꞉5305:9:5551

Question

I just created a new project and have run it for the first time using F5 or Ctrl + F5. The result in Chrome is:

The site can't be reached

err_connection_refused

I checked the option at the breakpoints for "Exceptions caught" and the following error is displayed.

Without "Exceptions caught" checked, the next error raised:

I tried to run "ng s -o" from the terminal and all work fine. The site is working well on port 4200, but I like to debug.

Here is my launch.json file, all by default:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "type": "pwa-chrome",
            "request": "launch",
            "name": "Launch Chrome against localhost",
            "url": "http://localhost:4200",
            "webRoot": "${workspaceFolder}"
        }
    ]
}

Why is this happening?

Answer 1

I had the same issue and the problem was with the URL. It was https://localhost:8000; in place of http://localhost:8000.

So try checking your URL and routes.

Answer 2

This misleading error message seemingly has nothing to do with Chrome or any deprecated functionality. It can have many root causes and seems to occur whenever connectivity can't be established.

I got this while following the React tutorial for Visual Studio Code. In that tutorial you start by creating a template with npx and then running it with npm start. That worked, and I could see that it was using http://localhost:3000 for the URL in the browser.

However, when I changed the code as the tutorial requested and set a breakpoint to debug, I got the error in the OP's post, both with Chrome and with Edge.

Visual Studio Code was creating a default launch.json file for debugging and populating it like this:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    "version": "0.2.0",
    "configurations": [
        {
            "type": "pwa-chrome",
            "request": "launch",
            "name": "Launch Chrome against localhost",
            "url": "http://localhost:8080",
            "webRoot": "${workspaceFolder}"
        }
    ]
}

And I needed to manually change the 8080 to 3000 which fixed the problem.

The key for me was configuring the breakpoint to catch the exception like the OP described (note - you can only configure that with the Debug icon selected in the far left icon menu). While the emitted error message is still the misleading "deprecated" one, there was a message that "the site can't be reached" which you can find if you dig a little - as shown here:

I imagine that practically any configuration issue that causes the connection to fail will cause this error. So firewall issues, missing host program, bad configuration (like mine), etc.

Answer 3

I also had this issue and none of the solutions listed were helpful. However, the problem was rather easy to solve.

Just go into the Network tab of the Chrome Developer Console. Be sure that the connection is on No throttling and not Offline.

Answer 4

My server was just not running locally. :) Starting localhost solved it.

Answer 5

Instead of launching your application using the option "Launch Chrome against localhost", rather set your application name for launching - Resolved.

See the attached image for more context.

Answer 6

In my case, it got resolved by closing the browser and recompiling the app.

Answer 7

I had this same error and I resolved it by turning off my plugins. Specifically a CORS plugin I have been using.

Answer 8

For me, the issue was a React/Next.js application was not running.

Basically, you have to keep the application running in a separate window/terminal to be able to attach the debugger. This is unlike the other application where it starts from debug console itself.

Answer 9

Try this:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "request": "launch",
            "name": "Launch Chrome against localhost",
            "type": "dart"
        }
    ]
}

Answer 10

I have seen a lot of solutions for this problem, but nothing worked.

After a little debugging and commenting out many parts of the code, I managed to locate the issue.

Basically, it occurs on the backend; not the frontend.

There was an infinite loop that kept responses stuck. Fixing that issue, solved it for me.

Answer 11

I displayed a similar message in my debug console and the problem was that the local web server was turned off and therefore unreachable.

I turned on the server in the virtual machine and the app started working again :-)

Answer 12

In my case, I had a Blazor solution and began receiving the "Crbug/1173575, non-JS module files deprecated message". Besides this, I also received a 404 error for the Index.html file!

The cause was that I inadvertently removed the reference in the .Server project to the .Client project. The project compiled fine without the reference, but I guess ASP.NET Core does some sort of reflection-based analysis on the dependencies to dynamically build the route map.

Restoring the reference to the .Client project on the .Server project fixed the problem.

Answer 13

In my case, the problem was because port 4200 was taken by another application (Docker). As soon as I changed the port to 4201 by adding the next structure in the serve section of angular.json file the problem was solved.

"options": {
    "port": 4201
}

Answer 14

My problem was in the network settings of my Windows 10 computer, not on the browser. I have tried my URL in another computer and mobile browsers, and it was working fine.

So, I have fixed the issue by resetting my network settings

To do that, go to Settings → Network and Internet → Scroll down to Network reset.

Wait for 5 minute until it restarts.

Answer 15

I faced this issue while debugging in Visual Studio Code for an Angular application.

The probable causes may be the server is not up and listening to port. You may start the server manually by ng serve --port with port number. Also compare the URL in launch.json and compare the port number.

Answer 16

In my case it was caused by uBlock Origin. Disabling it on the website promptly fixed the error.

Answer 17

I think we should just remove the cookies in that URL:

Answer 18

I've tried many of the solutions suggested, and found someplace else this tip that was helpful:

I was unable to reach http://localhost:3000 from npm start run in a react app. So I tried: http://127.0.0.1:3000 and to my surprise it worked!

After some googling, I tried a suggestion to erase my browser cache, so I did it. All cached images and files (Google Chrome) and boom! It worked once again.

Answer 19

To add another angle to this. I named my JavaScript modules with .mjs. After setting my web server to serve mjs with MIME type application/javascript. I got the error

'crbug/1173575, non-JS module files deprecated.'

None of the answers here helped. To fix it I gave a path to the module.

From

<script type="module" src="xxx.mjs"></script>

To

<script type="module" src="./xxx.mjs"></script>

And the error went away.

Answer 20

I ran into this error on three separate Next.js projects. It was the same error in Chrome, Chrome Incognito, Firefox, and Edge.

It happened on a production build (next build && next start) and development server (next dev). After trying a number of fixes – ensuring I was on HTTP, not HTTPS, checking if the port was in use, deleting folder node_modules and running npm install, etc. – the thing that finally worked was restarting my computer...

Answer 21

For aiohttp.

I've stumbled upon this issue with an aiohttp server. By default it was running on 0.0.0.0:8000 The solution was to change the host and the port to localhost:8080 in main.py file: web.run_app(app, host='localhost', port=8080)