Allow underscores in Supabase storage bucket names (backward compatibility request)

Hi Supabase team,

Previously, it was possible to use underscores (_) in storage bucket names—even though it was noted as not recommended—and many existing projects, including ours, were structured with this naming convention. However, it seems that recent updates have restricted this, and bucket names with underscores are now rejected.

This change has introduced friction for teams migrating or maintaining legacy systems, as it breaks compatibility with setups that were previously valid. It would be incredibly helpful to either:

Re-enable support for underscores in bucket names

We understand the need for stricter naming conventions, but retaining backward compatibility (or offering a workaround) would go a long way for developer experience and long-term platform adoption.

Thank you for the amazing work you do—Supabase has been an essential part of our stack.

Best regards,