The details of the scene in question haven’t been specified, but The Wrap’s report says it was intended to tease a spin-off.
The problem is, it was filmed outside of Diesel’s purview, possibly fueling his angry reaction, demanding it be removed.
The feud between Vin Diesel and Dwayne ‘The Rock’ Johnson has been well documented at this point, becoming a story nearly as big as the two actors themselves, possibly even contributing to The Fate of the Furious‘ record-setting opening weekend box office take.
Leading up to the release of the film, both Johnson and Diesel began to shrug off questions about the feud, suggesting that it was either overblown, already resolved, or both, which sounds like a reasonable explanation.