Ok, should have noticed earlier that the calls to the private function _miab_post() never used the _needbase64_ or the __postContentType parameters. Parameters and code to handle them has been factored out.
Know I'm new to contorting to this project. I i've broke conventions please let me know what I've screwed up and I'll set it right as quickly as possible.
Propose this as a new DNS-01 validation script to dynamically add challenge DNS records to MailinaBox (MIAB) DNS. MIAB uses a custom DNS API to manage external DNS records.
The script was originally written by Darven Dissek and can be found in his repository: https://framagit.org/DarvenDissek/acme.sh-MIAB-DNS-API/). This has been forked and some slight cleanup applied and change shebang to UNIx shell. The forked repository can be found here: https://github.com/billgertz/MIAB_dns_api.
Wrote to Darven but received no reply. Support for this script has been submitted to the OPNsense project via this pull request: https://github.com/opnsense/plugins/pull/1531
Bill Gertz