Outlook link checker cancels an event.

[Konafets]

Extension version

6.5.2

Short problem description

If cancellation is allowed, the extension adds a cancellation link to the confirmation mail. When a user clicks it, he will redirected to the TYPO3 instance to cancel its participation. "Behind" the link is no button which a user has to click to cancel, instead the cancellation is happening by clicking the link.

The issue occurs when a user uses Outlook and clicks the link. In this case Outlook performs a link check (for reasons I do not know) and activates the cancellation. When the user "arrives" at the page, a message informing the user that the event was not found or that his participation was already cancelled.

Expected behaviour

I think, the default template should contain a button which must be clicked to cancel.

Server configuration

TYPO3 version: 11.5.32

PHP version: 8.1

[derhansen]

I will not change the behavior of the extension, as the suggested solution then also should be applied to all other links in emails, which lead to a actions in the extension (e.g. confirmation, opt in). Basically, there are already double opt in features in the extension (e.g. on registration) and having the described solution with the button "behind" the link would actually result in a tripple opt in scenatio which most likely will distract users.

I have seen similar problems with e.g. ext:femanager, where the account creation is not possible, because some spam filters checks links in email content and thereby calls the action behind the link. Actually this not really a good idea, since this e.g. also results in fake newsletters subscriptions with opt-in link would result in users being actively subscribed to newsletters, since the "link check" confirms the subscription.

[Konafets]

Thanks for the fast response. I will propose my solution to the customer and if approved implement it in a custom extension.

[derhansen]

6 months later and I now think different, since those spamfilters and link checkers are really getting annoing and lead to unwanted behavior (not only in sf_event_mgt, but also newsletter systems).

In case of sf_event_mgt (v7 only), I will add 2 new optional actions (see #1237), so user must double confirm/cancel the registration in a new view