Block selection box is darker compared to older versions

i have this too

Ditto, it's very distracting.

If you look on Minecraft Wiki, this is intended.

This change being listed on the wiki does not mean that it's intended. The wiki is written by players, not Mojang.

This might very well be just another one of the many rendering issues in this snapshot, though I personally don't think that this change would be too bad if it would be kept. But I know that quite a few people disagree with that.

Shame this is fixed, I would have much rather it was kept as an accessibility option.