Answer
You can add custom syntax definitions to Textastic by using TextMate bundles or Sublime Text packages. See
https://www.textasticapp.com/v10/manual/customization/custom_syntax_themes_templates.html
This TextMate bundle should work:
thank you, that worked. The package only provides syntax highlighting, though. Better than nothing :-)
Customer support service by UserEcho
You can add custom syntax definitions to Textastic by using TextMate bundles or Sublime Text packages. See
https://www.textasticapp.com/v10/manual/customization/custom_syntax_themes_templates.html
This TextMate bundle should work:
https://github.com/jezcope/Org.tmbundle