Mailing Unsubscribe Form: Show if email is already unsubscribed

[mattwire]

Overview

This cleans up messaging on the unsubscribe form so it is clearer (at least in english) what the current status is.

user@example.org is unsubscribed > user@example.org has been unsubscribed successfully
user@example.org has been unsubscribed > user@example.org has already been unsubscribed

Before

Click link in email:

Unsubscribe form shown.

Click unsubscribe:
Message is user@example.org is unsubscribed

Click link in email again:

Message is user@example.org has been unsubscribed.

After

Click link in email:

Click unsubscribe:

*Note: ignore the mailing error - that's related to #21173 and the confirmation message here is now clearer because the unsubscribe WAS successful but the email confirming that unsubscribe failed to send.

Message is user@example.org has been unsubscribed successfully.

Click link in email again:

Message is user@example.org has already been unsubscribed.

Technical Details

Comments

[civibot]

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[agileware-justin]

Great PR @mattwire

Would really like to improve the user experience in this area, have raised a Gitlab for a discussion, https://lab.civicrm.org/dev/user-interface/-/issues/42

[wmortada]

This makes sense to me. Thanks @mattwire

[mlutfy]

Breaks translations, but worth it imho.

@mattwire Could you resolve the conflicts? (doing it via the Github IDE gives me rather odd results)

[mattwire]

@mlutfy I've fixed the merge conflicts