Switch Between Directories in Power BI Service

Problem Statement

Unlike Azure Portal, wherein we can switch across directories.

And in PowerApp via the respective Portals.

Is it possible to switch between directories (tenants) within Power BI?

Solution

Whenever one logs in within the Power BI portal: app.powerbi.com, the account gets logged in within the default directory/tenant in which the account is created.

Unfortunately, there is no option in the Power BI portal to switch across directories directly (tenants to which the Account is added as a guest user).

1) If you are a guest in some host's tenant (directory) then you need their Customer Tenant ID (CTID) to log in to that host Power BI instance.

2) Once you have the tenant id (CTID), simply provide it to the URL as PowerBI CTID Url

https://app.powerbi.com/home?ctid=<<(ctid)>>

and then this will sign you into the (necessary host tenant) PowerBI.