I have installed a few extras via Installer but removed them later. However, Installer has not been able to remove them successfully. For example, site log is now full of error messages of partially installed/removed extras.
How could I remove manually all traces of these extras? Where is the data stored?
Removing the value {locator":{"path":"[[++core_path]]components/locator/model/"} from extension_packages system setting helped.
Thanks @anton-tarasow.