You would think that when triggering a Ghast, you can hop out of the way or hide behind a wall out of sight so that the Ghast will reset, right? But instead what happens sometimes if you escape the Ghast as it is about to shoot, the Ghast will stay charged with its fireball and will instantly shoot you the moment you are in sight again without any sound. This does not happen on Minecraft Java Edition so I'd assume it is safe to say that this is a bug that has not been patched yet. This has also existed for quite a while and has been fixed by coders using behavior packs, but for a non-modded experience, this is an issue with the nether.
(Sorry for the laggy gameplay, I didn't have stuff configured well for recording)