Non-email generating comments in Service Desk issues

Description

As a EEP user of Service Desk, I want to be able to comment on a generated Service Desk issue and not have it generate an email back to the customer, so that I can discuss the issue internally without fear of releasing information to the customer that is meant to be an internal discussion only.

Proposal

Enable a comment to be "non-email generating" by default and require the commenter to actively check a box before an email would be sent to the originating customer.

cc @victorwu

I think that even if you do not mean to go as far as a Customer Database in Service Desk you probably ought to consider that some comments are likely to be internal discussions and not every comment ought to generate an email back to the issue originator.

changed title from Private comments in Service Desk issues to Non-email generating comments in Service Desk issues

Thanks @gsmethells. This is indeed something we would want. I updated the title + description to be less implementation specific, and more focused on the use case. Because we already have an issue discussing confidential comments (https://gitlab.com/gitlab-org/gitlab-ce/issues/23436). They may or may not overlap. So let's not assume that for now.

I think your suggestion of the default is the right way to go.

@lbot : I think this is a no-brainer right? And a good next meaty feature?

changed milestone to %Backlog

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Sure @victorwu

I had mentioned the new Service Desk feature to our Support Manager, but she freaked out about this very feature (and the need for the Customer Database one too), so we cannot use Service Desk as it is right now and will need to send our to AutoTask instead for now. But if both of those came to fruition, then I would certainly consider moving up from EES to EEP.

@victorwu also, the default of not sending could itself have a default in the project Settings. But, honestly, better safe than sorry when it comes to quick comments leaking out to customers. There is no retract feature for email.

Thanks @gsmethells for checking out the feature and giving us that valuable feedback!

@victorwu I agree. Internal comments are a huge part of our workflow to keep context into the ticket.

mentioned in issue #2284 (closed)

changed milestone to %Next 2-3 months

changed milestone to %Next 3-6 months

mentioned in issue #3445