Custom Okta Account Chooser

Questions
1

Is there an official HTML widget that allows user selecting Okta account & domain,
like on the Okta Account Chooser page (https://login.okta.com/)?

I would like to place it on a custom (multi-tenant) login page
in order to generate SAML login URL using chosen Okta domain name
and login user into the SAML application.

2

I’m not aware of any, but you can build one for sure

3

How do I obtain the list of Okta accounts user has ever logged into?
Where is this info stored in browser?
Cookies, local storage?

4

Oh, I understood you differently. I thought you were talking about different okta tenants, my bad