setOptions only setting id and nothing else?

[TomDeSmet]

Environment *

npm ls vue-gtag: [email protected]
npm ls vue: [email protected]

1. Operating system: Windows
2. Browser and version: Chrome 129.0.6668.90

Description *

I'm using VueGTag with bootstrap: false.
Then I use setOptions and pass the id and user_id properties in the config object.
After that, I call bootstrap().

Everything seems to work, but the config event I see in the GA debug tools does not contain the user_id property. Nor any other property I set in there (e.g. language).
The setOptions seems to work as the id is passed correctly because everything is getting tracked (if I omit that it doesn't start tracking or throws an error on bootstrapping).

So I'm not sure which event has the user_id and if it is even being sent...

Expected behavior

The config event has this: "config", "G-XXXXXXXXX", {send_page_view: false}
But I would expect something like this: "config", "G-XXXXXXXXX", {send_page_view: false, user_id: 'ABC' }