gruva

My point was that the spawning in java happens all over the place within the loaded area around a player but mobs outside 128 blocks despawn instantly (in java). 64 to 128 they're just immobile. I'm not saying this is good for bedrock as the distance of 44 blocks is painfully small but it is a similar set up as java, at least what I can see of it currently. This is why I'd assume it's WAI.

That is what happens in java so....

@Theresa no one called it a fix, I just commented that it'd changed. If it had been considered a fix then this bug report would have been closed. 

@dcn, no spawn radius was the full ticking area. And mobs don't despawn unless the light level is 7 or higher.

Not really, you still have the density caps to deal with. 

Not sure it's been commented here yet, but, the spawning has changed. Mobs now spawn in a sphere around the player. Everything else remains the same. 

Sadly it sounds like you got caught up in an error from a week or so ago. Somehow xbox players got entered into the betas whether they'd opted in or not. Your world is not likely to be playable until 1.11 releases fully. Personally I have no idea how this issue came about but there were a good few apologies from some of the devs on this at the time.  

Was it a water bottle?

Items take 5 minutes to despawn if they're being ticked (loaded/not too far from the player). If you think they despawned much faster than this then could you give us some more details on the conditions that made this happen? Otherwise this ticket will be closed as invalid. 

https://streamable.com/m467j as an example from another player, getting low, low fps 

Can confirm, I can't see any exploits with this but it is clearly a bug. After brewing the empty bottle it won't stack with other empty bottles so it's clear that the nature of the bottle has changed during the brewing. 

Sounds like you're hitting the hard cap of 200 mobs in the loaded world. If 200 mobs get loaded then you can expect zero new spawns.

Thank you for the extra detail, it has helped someone else get their game back up and running properly. 

Feels like the blast power of the heads has been massively nerfed, a trapped wither in cobble can't even break out.

It's on the Wiki, https://minecraft.gamepedia.com/Spawn
just look for the bedrock subheadings

testing what though? we know what the mechanics are, it's just not what everyone wants. also we know that the mechanics are being considered for an overhaul.

he slime chunks not spawning may be related to a different slime related bug which will be addressed in 1.9.

ok got you, the slime spawn in swamps have a different set of spawning rules to those in slime chunks. Lighting up swamp land will block the slime spawn in swamps. 

to be honest, I did a few slime tests related to another bug and I have been seeing slime spawns at high light levels on pumkins. Could this be a time of day issue? I'll run a few more tests to see if I can replicate.

This has to be WAI as each shulker box should have a different ID so the game can identify what contents it should have.

I've not been able to replicate this issue, would you be able to upload a world file where this is happening?