Is it possible to include a “private” copy of ACF in a premium plugin? A version that would remain at the same version it was shipped and would not collide with a potential already installed ACF PRO instance installed by user?
If not, which instance of ACF PRO takes over, the one installed by the user or the one included in my plugin?
You can’t have 2 version of ACF, one of them will be used. The one that is used is the one that is loaded first. The order that plugins are loaded is set by WP and can change. The order they are loaded has something to do with the order they are installed/activated. Honestly, I haven’t been able to figure out the load order exactly and it’s a coin flip.
Any plugin you build needs to be able to run on the most recent version of ACF and be update-able. I know that E makes ACF so it can be included in themes and plugins, but I’ve never been a fan of doing this as it usually means issues for the user. Just tell me I need to also buy ACF so that I can keep it updated.