Currently, Studio doesn’t support adding 3rd party or custom script to the campaign.
But if you have paid for a subscription plan, we may assist you in making 1 simple manual update, once a month. With this, you can request us to add a 3rd party or custom script to the campaign.
Alternatively, you can purchase the Technical Support package, then we may support you with multiple simple manual updates during that Technical Support period.
Please contact us at firstname.lastname@example.org when you want to do so.