Hey everyone, i have a problem when i enable v4_gtag for analytics instead of v3_analytics, i need GTag for Google Optimize but i keep getting an error that gtag is not a function. i am calling the gtag function inside a plugin js file, can someone provide more context on why this isn’t working ? here is a sample of how i’ve written the code, Thank you in advance export default { name: 'common-init', after: 'inject-objects', initialize() { gtag('event', 'optimize.callback', { name: settings.optimize_js_experiment_id, callback: (variation) => { console.log(`Variation: ${variation}`) } }) } }

Where your gtag function define?

i would assume its defined as part of Discourse when. i enable gtag from settings

so i still need to add the GTag importing script manually somewhere ?

Seems gtag is define at runtime under window object, so you don’t have to import it again but call it in runtime like window.gtag. https://github.com/discourse/discourse/blob/master/app/assets/javascripts/google-universal-analytics-v4.js

i was able to define the function on startup and i think discourse is gonna redefine it when it loads which is currently working ok, but i have another problem now, when i add my ga tracking code in ga universal tracking code it still includes analytics.js even though i am using v4_gtag, is this an expected behavior ? won’t. that make an issue of sending duplicate events ?

Using Google Optimize in a plugin initializer JS

Product Support

hawm (Hawm) March 31, 2021, 8:29am 4

You will still need to import even it define at somewhere already.

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Using Google Optimize in a plugin initializer JS

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