Split display link options into 'flag' and 'unflag'

That would require major changes to the JavaScript parts of the module, and isn't something I have the time or the skills to do.

Hence it's only going to happen if users who want this feature work on a patch. Marking as postponed; please set it to active and assign to yourself if you want to do that.

Tagging.

Retitling.

#1291670: Provide a live (iFrame) preview of various flag texts in action should probably get done for this too.

Not sure this is going to happen on 8--4 either...

I've been pondering this lately, and I'm now starting to think we could feasibly do it for 8x4x, if we manage to get it in before we start making beta releases.

It's actually a fairly small change, I think:

- add 2nd property to the Flag config and rename the existing one (or indeed, convert the single link type config field into an array)
- change the link output code to take this into account when rendering a link

The benefits are that you can create different combinations of flag link types, so for instance:

- AJAX or reload to flag, but confirmation form to unflag (prevent accidental loss of data)
- AJAX or reload to flag, with edit / delete form on unflagging (don't slow users down when flagging, but allow adding of data afterwards)
- form to flag, AJAX to unflag (require data entry on flagging, but unflag quickly. Use case: spam or abuse flag, where an admin will want to quickly remove a flagging that shouldn't be there.

I'm tagging this as release blocker in the sense that we either need to tackle it before release, or postpone it for the next major version.

Seconded.

Interesting. I was thinking through something similar while I was working on link displays earlier today. I wonder if there's a way to leverage the plugins to provide the admin with a grid where this could be configured. Something like:

| Location | Flag Display | Unflag Display |
|---------------- |------------ |------------ |
| Field | Ajax | Confirm Form |
| Contextual Links | - None - | - None - |
| Edit Form | - None - | - None - |
| Teaser Links | - None - | - None - |
| Full view links, ... | - None - | - None - |

As a stretch goal, display plugins could have a way to opt out of certain locations (ajax in the contextual links for instance). I could probably spend some time on this if it's something the maintainers think is viable for 8.x-4.x.

That's something I've pondered too, but I think that sort of direction would be better served by moving the link type configuration out of the Flag entity:

- Contextual Links: these are always just links, so link type doesn't apply here
- Edit Form: same, this is always a checkbox
- Field: it would make sense to have the configuration in the entity display admin UI, alongside 'real' fields. AFAIK though there's no system in core yet for configuring pseudofields. (Though I have noticed that Media Entity module adds a 'Thumbnail' pseudofield to its entities -- we could take a look at what that's doing.)
- Node/Comment links: these are a bit of a special case. But again, what would be nice (but even less likely to happen in core soon!!!) would be configuration of the node links over in the node display admin UI.

We had a case where we added fields to a Flag, so we wanted to require confirmation on unflagging since this might result in the user losing the data entered into those Flag fields.

To do this, we created a new "Conditional Confirm Form" link type that allows administrative users to set Flags to use the Confirm form only under certain conditions. This seemed like it might be useful, so we broke it off into its own module:

https://www.drupal.org/project/flag_conditional_confirm

It does use the current Flag configuration UI, so an administrator can set when the Confirm form should be show. It also allows for implementations of a hook_flag_conditional_confirm_confirmation_required() function.