Updating at the end of 2025 (after not updating for a year) I noticed the new themes. In the old ones I used the custom fields like {{ custom_fields.FirstName }} and {{ custom_fields.Organization }} in the theme. That is still working for my Sales Quote/Invoices but it stopped working for email templates and, I discovered today, reminder letters. I tried several liquid code variances. But apparently something changed. Please help me out with the correct syntax for using custom fields in documents. Thank you!