Hello how can i check if Javascript growthbook is serving me a variation instead of a fallback? Currently variations look like this

// control
{
placement_1: {enabled:false},
}

// variation 1
placement_1: {enabled:true, url: variation1_url}

// variation 2
placement_1: {enabled:true, url: variation2_url}

Fallback looks like this

{
placement_1: {enabled:false},
}

As you can see the fallback value and the control value is exactly the same. So sometimes i'm not sure if i'm getting a control value or a fallback value

You can debug a number of ways - if the user is being served an AB test, that will cause the trackingCallback to be fired