Populate a Date field in Leads_FormPage from AddTaskMiniPage

Hello Community,

We have created a button in Leads_FormPage that opens AddTaskMiniPage

Code in Leads_FormPage that opens the AddTaskMiniPage

  {
        request: "usr.OpenTaskModalPageRequest",
        handler: async (request, next) => {
            const handlerChain = sdk.HandlerChainService.instance;
            await handlerChain.process({
                type: 'crt.OpenPageRequest',
                schemaName: 'AddTaskMiniPage',
                $context: request.$context,
                scopes: [...request.scopes]
            });
            return next?.handle(request);
        }
    }		,

Our end goal: We want that upon the Activity is created (Save button clicked in AddTaskMiniPage) the value of 'Start' field in AddTaskMiniPage, is copied to another Date field in the Leads_FormPage.

How can this be acheived?

Regards

Sasor