How do I trigger a Goal Conversion when a user clicks a link, using Matomo Tag Manager?

The recommended method for tracking goal conversions is to use the Goal Triggers that can be setup when creating a Goal as explained in the Goal Tracking User Guide

With Matomo Tag Manager, you can track goal conversions for specific links, or for links that contain specific parameters or strings.

For example, a visitor may click: example.com/my-goal (your URL can contain a simple path as shown here, or a more complex one such as example.com/my-goal?success=1)

1. Create your Goal in Matomo and make a note of the Goal ID.
2. In Tag Manager, go to Triggers and choose the All Links Click as the trigger type with a custom name such as Signup Link Trigger.
3. Add the conditions that define when the goal triggers, for example Click Destination URL contains my-goal. If you have other URLs that contain this string, then you may need to add additional conditions to only trigger on these specific URLs such as a regular expression/regex.
4. Note that this trigger will only fire if all of the conditions specified here are matched, so you will not be able to add each unique call to an action link as a trigger.
5. Optional: If you only wish this goal to be triggered from a specific page on the website, you can add an additional trigger (for example, to track this goal conversion from a specific section of our website, such as the “shop” section):
   Page Variables > “Page URL equals https://example.com/shop”
   
6. Create a new “Matomo Analytics” tag with name “Signup Link Tag”
   Tracking Type: Goal.
   Goal ID: The Goal ID.
7. Configure the tag the Execute when the “Signup Link Trigger” is triggered
   
8. Test the new Tag and Trigger using the preview mode on the page you wish to use it to ensure that the goal is being tracked correctly.

Once tested, you can publish the container to your Live container version.