AppBridge issue - Message origin does not match app origin

[sergeyantonuk]

Hi everyone!
I am developing App with JWT auth where I use osiset "feature/cookieless" branch of package as fork.
Our frontend is built on react + polaris, backend - this is just API which uses the osisset package.

We use SPA on the architecture where the frontend and backend are on different hosts.
I use ngrok for development for my front and back end.

To implement JWT, I need to initiate an AppBridge on the frontend. To do this, I disabled the AppBridge in the osiset package, since here the AppBridge initialization are performed in the templates.
For testing I just copied the AppBridge initialization code from templates(default.blade.php and token_handler.blade.php) to my frontend, which is located on a different host.

Next I set the backend host as App Url in the App setup (partners.shopify.com -> AppSetup)

In other words, first the index page of my backend is loaded, from which there is a redirect to the frontend, with query parameters where I pass api_key and shop_origin.
After this frontend initialize the AppBridge and then, for any requests to my api, the frontend will transfer a fresh token in the header.

But I got an AppBridge Error like on screenshot:

"Message origin https://frontend.host does not match origin https://backend.host app"

I understand that this is done for security purposes, but how can we disable origin checking for AppBridge for the development process?

Also I tried do to do it through a persistent subdomain created on ngrok, something like this:
be.myapp.ngrok.io - backend
myapp.ngrok.io - frontend

but no success as well.

Can someone give me a hand?
thanks in advance!

Context
Package - "feature/cookieless" branch of package as fork.
Laravel Version: v7.19.1
PHP Version: v7.2.24
I use ngrok for my front and back end