[Vuejs]-Vue: Mysterious ghost props?

This line seems the likely cause, though without seeing the code for modalMeta it’s difficult to be sure:

v-bind="modalMeta"

This is using the object v-bind syntax, so whatever properties exist in the modalMeta object will be passed as props to the component.

See:

• https://v2.vuejs.org/v2/guide/components-props.html#Passing-the-Properties-of-an-Object
• https://v2.vuejs.org/v2/api/#v-bind