Struggling to start new project with hydrogen, session_secret error.

[SefSyndicate]

This was working for me last week but I'm not sure what has happened since, I've decided to embark on a new project and new store.

Created shopify partner account
Created development store (to test and build)
Ran "npm create @shopify/hydrogen@latest" in terminal
Options chosen:

• Use sample data from mock.shop
• Typescript
• Tailwind v4 alpha
• npm
• scaffold routes and core functionality
• subfolders

Opened code editor, .env file.
Installed headless app
Extracted storefront and customer account API, stoefront ID and domain
Applied API information to .env file.

my npm run dev result in http://localhost:3000/:

Error: SESSION_SECRET environment variable is not set
at Module.createAppLoadContext (C:/Users/sefni/Desktop//app/lib/context.ts:19:11)
at Object.fetch (./server:12:58)
at handleRequest (Users/sefni/Desktop//node_modules/@shopify/mini-oxygen/dist/vite/worker-entry.js:1098:48)
at withRequestHook (Users/sefni/Desktop//node_modules/@shopify/mini-oxygen/dist/vite/worker-entry.js:1053:26)
at Object.fetch (Users/sefni/Desktop//node_modules/@shopify/mini-oxygen/dist/vite/worker-entry.js:1099:38)

[wizardlyhel]

In your local .env file, just add

SESSION_SECRET="foobar"

If you are deploying to Oxygen, SESSION_SECRET environment variable should already be defined for you

[SefSyndicate]

You are a star, Thank you!

Have a great week.