unable to open the sample helloworld page

[kishor]

i created the sample project  the hello world when ever i visit https://localhost:9000  its gives me a whole project files in the browser instead of hello world any idea what it could be  ?
im attaching the screen shot for reference

well im trying to create a custom extension

[dilipborad]

Hello @kishor,
I can understand that you're trying to create an Airtable extension block.
Follow these instructions https://airtable.com/developers/extensions/guides/hello-world-tutorial

This is not run on our local browser but it's run on the Airtable extension panel where we added that custom extension.

I hope this helps you.
👍

[kishor]

i did done those steps, even on the documentation itself says that its runs on the local host cause its simply a react app
well its also points index.js in front end like this
{
2 │ "version": "1.0",
3 │ "frontendEntry": "./frontend/index.js"
4 │ }

but i dont actually get this point that you mentioned 
"   This is not run on our local browser but it's run on the Airtable extension panel where we added that custom extension.   "

i will be greatfull if you can provide more information 
thank you

[dilipborad]

@kishor 
When we run https://localhost:9000 to our browser on a single tab then It's run independently on our local browser.

However, these custom extensions are not independent. They are dependent on the airtable.com domain.
So it needs to run within Airtable to use predefined UI block, use loaded data and some settings that are within the Airtable domain.

I hope you can understand now.