Finished with error: Failed to establish connection with the application instance in Chrome

> Finished with error: Failed to establish connection with the
> application instance in Chrome. This can happen if the websocket
> connection used by the web tooling is unabled to correctly establish a
> connection, for example due to a firewall.

I am getting this error, when i run my flutter web application on chrome browser. I also turn off my firewall even that didnot solve my problem.

What will be the possible solution for resolving this eror?

Temporary Solution that i had tried:
I had this issue when upgrading from dev channel to master channel.
what i did to solve this problem is, clean my project's build cache (flutter clean), then run the project using release mode.
After that, i can run it on debug mode.

This solved my problem temporarily and after some time i still facing the same issue. And implementing the same solution didnot solve my problem.

I'm glad that you solved the issue,
when upgrading version or changing channel
it's generally a good idea to run
`flutter clean`
and if needed
`flutter pub cache repair`;
I believe there's no action to be taken.

I've been facing this problem as well. I always get this error when i run 'flutter run -d chrome' the first time, but if i run it again for the second time, it runs perfectly.

You have to download Dart Debug Extension from chrome to run Flutter app on web

When working on VSCode in Windows in Flutter beta channel, use the command `flutter run -d chrome` to run in Chrome instead of F5.
Works every time for me.

Use command:

flutter run -d --release

Use below commands:

flutter channel master
flutter create --web
flutter config --enable-web
flutter devices
run -d web
flutter clean
flutter run -d chrome

use some commands like below ----->>

flutter run -d chrome --release

or

on Editor **Android Studio** or **Intellij** goto -> **Run** >> **Flutter Run In Release Mode**



these are work for me

to enable web---->

flutter channel beta
flutter doctor
flutter config --enable-web (for a ready project)

and

flutter create --web

for creating a project

It mostly has nothing to do with flutter but, it's either because you have log your computer in safe mode.

In my case shift key was stuck and I had no idea I was in safemode.


Or perhaps you need to check your firewall

- system preferances>security and privacy>>firewall
- click the lock below and enter your system password
- and then click firewall option [enter image description here][1]
- In there add your editor to allow internet connection (android studio Or VsCode)

It looks something like this:

https://www.google.com/url?sa=i&url=...AdAAAAABAD


[1]:

I face the same problem for the first time I want to run the web app, but when I re-run the web app ,it works fine.
Try to re-run