Capabilities/block/quickmail:cansend
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If a user has this capability, then s/he can see the Quickmail block in the course and use it to send emails to other users in the same course.
Note: You are currently viewing documentation for Moodle 3.6. Up-to-date documentation for the latest stable version of Moodle is likely available here: Capabilities/block/quickmail:cansend.
If a user has this capability, then s/he can see the Quickmail block in the course and use it to send emails to other users in the same course.