I am redeveloping a site and was wondering if I could activate the child theme only on one page while the upgrade is happening or does it have to be live on the whole site?
The theme has to be active on the entire site as far as I know. There may be a plugin out there that allows you to switch between themes, but I’m not sure it would be a good idea to do so.
Thanks For that, I didn’t think it was possible but just as i was reading your reply, I though of a work around which you have already given. and that is to make a custom header and change the individual pages in layout.