What API to use in webform for sessionStorage

I’m trying to pass data from web form to other page using sessionStorage. There are several fields I’d like to get value from.

What api should I use?
In the docs I can see 3 event triggers:

  • frappe.web_form.on → if use this, how to accomodate several fields?
  • frappe.web_form.validate → this cause the form can’t be saved (popup msg saying form can’t be saved, please check your data)
  • frappe.web_form.after_load → can’t use this as the form still empty when it’s first loaded.

Currently I use validate and return (true) to allow it to be saved.

Please advice… thank you

ps: it is not mentioned in any docs but I see we can use frappe.web_form.get_values to get value from multi fields.