Compared are the Original Version and the Director's Cut.

The differences:

1 alternate scene

Heart-Shaped Box is a single release of Nirvana's third studio album In Utero (1993). Founded in Aberdeen (Washington) in 1987, the band's big break took place with the Nevermind album 5 years later. They split up in 1994 after Kurt Cobain took his own life in his house. Even after more than 20 years, there are still speculations about his motive and rumors about a murder for hire among fans.

For a long time, there was only one version of the music video to Heart-Shaped Box. Meanwhile, a so-called Director's Cut with identical length is available on several sites. The difference is a single scene with alternate footage.

03:02 Min
It all starts with the beginning of the third minute when Kurt is singing: She has me like a pisces when I am weak. I've been locked inside your Heart-Shaped Box for weeks. I've been drawn into your magnet tar pit trap. I wish I could eat your cancer when you turn black.

In the Original Version, he is sitting on a chair while the two other band members Dave Grohl and Krist Novoselić are sitting on a bed in the background. Krist has his arm on Dave's shoulder - both are looking at the camera.
The Director's Cut however shows several shots of Kurt lying motionless in a field of flowers with his eyes closed. Furthermore, there are intercuts to a big woman wearing a costume with wings and the little girl dressed up as a member of the Ku Klux Klan. Among other things, that girl is pushing a wheel chair or standing in front of a wooden cross.
no difference

Original Version:

Director's Cut: