If you have an extension where the manifest.json-file is missing the 'extension list' commands doesn't return a result.
Instead the following error-message appears:
preside-terminal> extension list
Error processing your request: key [title] doesn't exist
This is not a big issue, but could confuse people.
The 'extension list' command should work as expected but maybe only shows the foldername of the extension.
The other extension commands (enable/disable) work as expected.
Well, put a manifest.json file in your extension folder.