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Create a new tag in google tag manager https://support.google.com/tagmanager/answer/12002338?hl=en
Click into tag configuration and choose Google Analytics: GA4 Event.
For Configuration Tag, select None - Manually Set ID.
For Measurement ID. enter your google analytics Data Stream Measurement ID eg: G-********** or similar.
To subscribe to the Form_Context (case sensistive) variable click into event parameters then click on the lego plus icon
Next Click the plus icon at the top right of your screen to create a new variable.
Click into Variable Configuration and select Data Layer Variable
In data Layer Variable Name type Form_Context -- This is case sensitive
Save and give your variable a memorable name eg Form_Context
Now Add form context Form_Context (the variable you just created) to your parameter name and parameter values by selecting it from the list provided when you click the lego block icon
Next click into triggering and click the plus icon in the top right of the panel to create a new trigger.
Click into trigger configuration and select Form Submission from the User Engagement section.
Save and give your trigger a memorable name like Form Submission Trigger
You are now all set up to track form submissions with GTM and GA4
If you would like to have more control over the tracking you can read on and instead subscribe to the custom tracking method based on submission success selectors.
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