How to hide a field if an initial value is passed in a specific context.

Does anyone know how to hide a field if you're in a context where there is an initial value?

What I'm trying to do is to hide a field if an initial value is passed. Meaning if that the field has a predetermined value, the display of the field is not needed.

I ended up doing something very ugly! I checked the URL to see if I was in the context that I was looking for.

I have an entity called person, and the person must belong to a company. The person can be edited from the root of the menu, but it can also be edited when going to a company, and be selected as a sub-page. This means that the reference-field to the company on the person would only be relevant when not editing from a sub-page.

Ugly AF, but it works, and it will work as long a the URL structure does not change.