Just small example how you can verify vistor entered information using Rest API calls. This time visitor e-email.
https://doc.livehelperchat.com/docs/bot/verify-email-by-bot-and-rest-api/
https://doc.livehelperchat.com/docs/modules/forms/
https://doc.livehelperchat.com/docs/javascript-arguments/#department-scenario-from-widget-itself
https://doc.livehelperchat.com/docs/javascript-arguments/#department-scenario-from-parent-page
For update just follow standard update procedure For manual update it's update_237.sql
Avatars are generated using https://multiavatar.com project
For update just follow standard update procedure For manual update it's update_236.sql
Now you can chat with your site vistiors directly in Mattermost. You can see tutorial here
For update just follow standard update procedure For manual update it's update_235.sql