I'm trying to disable the module.
First drupal told me that there are fields that are using it, which contain data. So I went to corresponding content type and deleted the field.
Now I see the message in module description: "Required by: Drupal (Fields pending deletion)" that prevents me from disabling it.

I tried following:
- Flushed caches about 10 times or more.
- Run Cron about 10 times.
- Deleted the module out of the module folder manually and ran cron, then restored module from backup copy. Still was grayed out.

Can anyone advise how it can be disabled?