‘Your theme config.json file does not contain supportedFeatures’ message
It works very well, you only need to add this section to your config.json file in the following location: (Documents ▸ Publii ▸ sites ▸ YOUR_SITE ▸ input ▸ themes ▸ YOUR_THEME)
PS: maybe you override the config,json file and this is a reason why it does not work for you.
Do you appreciate the support you've received today? If so, consider donating to the Publii team by clicking here; we'll be sure to use your donation to make Publii even better!