Checkout UI Extension Configuration: Add field type dropdown in admin

Topic summary

Users are seeking guidance on implementing a dropdown/choice field type in Shopify’s Checkout UI Extension configuration settings.

The original poster notes that while the official Shopify documentation covers various field types, dropdown/choice fields are not documented despite being observed in use elsewhere.

Solution provided:
A community member shared working code for the shopify.extension.toml file:

  • Use type = "single_line_text_field" for the field definition
  • Add a validation section with name = "choices" and value = ["red", "white", "black"] to create dropdown options

Status: The solution was confirmed as working by the original poster. This appears to be an undocumented feature that requires specific validation configuration to enable dropdown functionality.

Summarized with AI on November 7. AI used: claude-sonnet-4-5-20250929.

Yeah, it worked.
Thanks