How to save relative urls in SharePoint Site templates

I have a webpart that has a link field, I want to keep all urls in this link field to be relative because when i save the site as a template and move it to a new environment, the absolute url is still pointing to the old environment which i don't want.

after i save it and try to edit it:

the fully qualified name is being stored, how can i avoid this ?

Thanks a lot.