Inboxtini does not store personal data, email content, or user accounts on its servers. Therefore, there is no "account" to delete.
This clears the active session and removes the access keys from your browser.
To ensure the connection is permanently severed on Google's end, visit your Google Security Permissions and remove "Inboxtini" from the list of authorized apps.
Once these steps are taken, Inboxtini has zero access to your data, and no residual personal data remains on Inboxtini's infrastructure.