KöMaL 2019 C1549

Let $F$ be the midpoint of a line segment $AB$, and let $Z$ be an arbitrary point on line segment $AF$. Draw a perpendicular to $AB$ at $F$, and mark a distance $FX=FA$ on it. Draw another perpendicular to $AB$ at $B$, and mark a distance $BY=AZ$ on it such that $X$ and $Y$ lie on the same side of line $AB$. What may be the size of the angle $XZY$?