I would like to make a URL segment only part of the URL if a Slug is existing:

domain.com/category/:category/tag/:tag?

The "/tag/" segment should only be present if a :tag slug was given, domain.com/category/:category should still be accessible if no :tag slug was given.

I tried with wildcards but did not have any success - is this possible via the slug parameters or do I need to go via the controller of the page?

Thank you in advance for any help and suggestions - appreciated