Given the Codepen example provided by the people behind the related web.dev blog post, transition-behavior doesn't have any influence on the transition of the display property.

According to CSS Display 4, any p value between 0 and 1 results in the non-none value. So the cards in the example should have a value of block for the display property for the time of the transition (0.25s) until it switches to none.

Sebastian

Looks like the animation of display is buggy, per our meta.

I'd go through it for CSS Animation as well.

So it seems like we intentionally disabled the animation of display property, per Bug 1371518 comment 0. So this may be related to supporting animation for display property. Once we support it, transition-behavior should work properly.

We probably have to fix Bug 1834877 first.