Is it possible to make an extension that specifically deals with the Form view, namely to add new form field types? I'm looking to try and make a linked record field that allows you to create new linked records, but everything in the Blocks SDK API mostly seems to revolve around manipulating the base itself, or making an extension-only view of a base's data.
Is this not possible? Is something like miniExtensions just building a whole new form view from scratch? (Note: I have looked at Fillout, but I'm mildly concerned about data privacy and would like to see if it's feasible through extensions alone.)
As you already mentioned above, the quickest & easiest & best solution is to use Fillout’s advanced forms for Airtable, which provides dozens of advanced Airtable features that aren’t natively available in Airtable’s forms.
Alternatively, to keep it all within Airtable, you can just create another Airtable form to create new records in the linked table. You can put a link to that 2nd form on the 1st form.
Or create a dummy linked record called “*CREATE NEW RECORD*”, and then have conditional fields show up when the user chooses that. Then, you can have an automation move the data into the appropriate table.