Building a TYPO3 extension in Extbase/Fluid

Extension Configuration/Plugin Options: TypoScript

Default values (Static Templates)

see this documentation on fluidtypo3.org on how to define default settings for your extension by using the so-called “Static Templates”

Specific values for your website

edit your website TypoScript template (TYPO3 Backend ››› List view ››› Root page ››› your template record)
add

plugin.your_extension.settings {

        specialConfigurationVariable = value
}
}

You can access these settings via {settings.specialConfigurationVariable} in your Fluid template or via $this->settings['specialConfigurationVariable'] in PHP

Set or overwrite settings in the content element form “Insert Plugin”

See topic Plugin Options (FlexForms) to learn how to make configuration available for editors in the content element forms of type “Insert Plugin”.