Your ROOT_URL in app.ini is https://git.cloudchain.link/ but you are visiting https://dash.bss.nz/open-source-mirrors/jfa-go/commits/commit/4104cb334e43e0b43e0ae307bc9c4a1057179236/mail/template.mjml
You should set ROOT_URL correctly, otherwise the web may not work correctly.
Variables are surrounded by {}, and initial (default) templates are
generated on demand from the plaintext version of emails. The custom
emails are intended to only be used if the user actually changes them,
as they lose the features of the default ones, such as tables.
Harvey Tindall