Mystery image inserted into email from Brevo

If I’m not mistaken, Brevo inserts a tiny image when I send an email through the SMTP relay.

Okay, no problem, but the image doesn’t have an ‹ alt › attribute, which lowers the spam score?

<img width="1" height="1" src='https://gbagieb.r.bh.d.sendibt3.com/tr/op/9Q03WvCppW2VHOFuIiUV8lQUMHSmPehvg1gr6ncGGj2NS-is4Z1w6M6t8zawhy2Xq6vW8Hx4tTN8FcOMtcoaTfJ3lq4E3WvfzdQisFcHNi2F3Absio-m10qUHsd5nWw'>

Anybody have any insight into that?