PnP SPFx PeoplePicker control works differently across site collections

Question

I am new to SharePoint framework and in one of the requirement I need to use the pnp spfx PeoplePicker, I have a List which is in different site collection. i.e. my List resides in Site A and I have a form at Site B which inserts PeoplePicker values in that list. when PeoplePicker values are inserted from same site collection i.e when form is submitted from the Site A where the List is, the values gets properly inserted, but when form is submitted from the different Site B or Site C the values differ in the List column. the value(user) submitted show different person or group in List column.

Is there a that a site context created for the selected site by and then that site context will passed in PeoplePicker context prop so it behaves same across site collections. I am stuck at this since a week now. any help or hint will be greatly appreciated.

Answer 1

This is happening because same user has different user Id in different site (collections).

The user Id & information is stored in hidden User Information List at site collection level.

You can read more about user information list at: User Information List in SharePoint All details

So here is what you can try:

Before saving people picker data in list in different site collection, ensure that user is already added in new site collection & get user Id from that site collection.

Then set person or group column using the ID you get from different site collection.