Multi select control isn't working on a pop window which is configured on a repeating grid operations tab, where as same configuration is working fine in normal section.
Steps to Reproduce
1) Drag & Drop a table in section
2) Configure a page list property in general tab.
3) Select Modal dialogue in operations tab and provide flow action details.
4) Open the section referred in flow action and configure a Multi select list control.
5) Create page list property
6) Drag & Drop in that section
7) Select control as "MultiSelectList"
8) Give the source as a Data Page for smart prompt.
***Moderator Edit: Vidyaranjan | Updated Categories & SR details***