It's been introduced recently, actually: https://www.msp360.com/resources/blog/mbs-now-works-optitune/

I saw it yesterday, I currently trying it in one of my servers but I cannot see it in mbs. Trying to configure backup but I cannot understand the way to configure emails as displayed in optitune.

Everything is configured on Optitune side, you just need to generate API credentials in MBS via the settings menu.

After that go to backup > settings in Optitune dashboard, enable "monitoring" and "install backup" options and there you can enter your MBS credentials.

Emails are configured in "Alerts" section.

Nope. It asks API username and API Password and asks also for email and password but it is explicitly asks not MBS credentials

Seems like there is some kind of misunderstanding. You need to enter MBS credentials there. API creds are generated under the settings menu in MBS portal.
Here's an example in attachment.

The explanatory help mentions other credentials. My credentials do not work. As I can see you have enter your details in monitoring and not in backup. I cannot find these settings you provided in screenshot.

Hey, Stratos, sorry for the experienced issues.

Let me please clarify how OptiTune integration works in MBS.

1. You need to go into the Settings section of the MBS Web Console (screenshot 1) and generate API credentials. Use these credentials when entering API username and API password.

2. You then need to enter credentials of an MBS user (not provider's or administrator's credentials). If you don't have any users yet, go ahead and create one in the MBS Web Console in the Users section (screenshot 2).

Hope that helps! Please confirm that everything is working properly.

How do I restore MBS and recover the all files.