Why flow retURL is not working in lightning in second end screen

Question

I have a simple flow in lightning which starts from a listview by checking multiple records and clicking a button to add the records to the flow. If the user does not select anything and clicks the button I show a screen message in the flow that a selection has to be made(Default Outcome) and return the user to the listview this is working fine. If a selection is made I create some records an show them a Thank you screen with the finish button, here the screen turns blank with only tabs vissible. Why does the return url does not work here.

Button

{!URLFOR('/flow/Add_Candidates_to_Talentpool')}&retURL=a0A?fcf=00B2p000009P40pXXX

Flow

Answer 1

This seem to be an salesforce issue: A mistiming issue in the way that Lightning-Out has been implemented by Salesforce.

Found in: https://developer.salesforce.com/forums/?id=9062I000000IHmLQAW

Answer 2

while creating List Button make sure window behavior must be like "Display in existing window without sidebar or header"
and URL be like :
/flow/Flow_Unique_Name?retURL=a0A?fcf=00B2p000009P40pXXX instead of {!URLFOR('/flow/Add_Candidates_to_Talentpool')}&retURL=a0A?fcf=00B2p000009P40pXXX
OR
if u want to redirect to Home page of List View of any Object :
/flow/Task_Date_Reschedule?retURL=/objectCode/o
objectCode are first three letter of recordId
for example if Account RecordID is '0010200000B7xnxAAB' then '001' is objectCode for Account Object.