Hey,
There is deep linking for checkout extensions ? (looking for something like there is for theme app )
Don’t think so, I just add this link and tell user to search for it:
shopify:admin/settings/checkout/editor?page=checkout&context=apps
Assuming you’re talking about UI extensions, then yes it is possible to deep link, but you cannot deep link to a specific extension. ATM Shopify requires the use of an extension collection, meaning you’ll need to create and organize multiple extensions…
Docs: UX guidelines