After the fix to MC-272563 no particles & etc. render behind it.
Under most circumstances you will only notice this on the explosion particles that spawn around the dragon and the end portal. Also the experience orbs that drop from it but that happens only on "Fabulous!" graphics setting.

Funnily enough the issue is visible in the minecraft.net article announcing the pre-release

Other things affected are all translucent blocks, clouds, lightning bolts, charged creepers, all particles, other dragon death animations (if there's multiple). Do note to preserve the fix to MC-272014 when tackling this.

Imo instead of all these bandaid fixes, someone should take the time to properly rewrite the death animation from scratch since it's very messy, and causes a lot of issues in vanilla and for mod developers, with them being just modified lightning bolts in the code and stuff.