Options for selectpicker

So it seems that in v9, the selectize javascript plugin is deprecated in favour of selectpicker. I cannot for the life of me find any documentation of the various options that selectpicker might have. I’m not sure whether this is a concrete-specific plugin or whether it’s part of bootstrap. The documentation seems somewhat elusive. Can anyone point me in the right direction?

The use case I have for it is for the user to be able to search for an entry, but have the ability to create a new one if their preferred value is not present.

Its bootstrap. https://github.com/snapappointments/bootstrap-select/


Many thanks. It was driving me nuts trying to figure that out.