How do I add an asset to every new theme that gets created?

[GetModa]

We are able to modify an asset for a specific theme and add a script tag as an asset to the theme through our Shopify application. But, when the store changes their theme, this script tag is lost.

How do I add an asset such that it applies to all new themes so that the new main theme also has this asset (script tag) available? I want this script tag to persist across themes (including new ones) and not just add this script tag (asset) to a specific theme.

[Jay_]

Would you enter it in the google analytics js field?