Found out this the hard way, but BetterPortals is not compatible with Dimensional Edibles.

Let's say we have the End Cake from Dimensional Edibles. Using it will force activate the "loading world" screen, ignoring BP's smooth transition. This in turn causes a desync where endermen are constantly popping in and out of existence. Parts of where you were before using the cake will show up over head.

The only way to get out of this state is to back out to the main menu and reload the save. But because in this state the game is also in a weird soft frozen state, specifically the auto saving function, it causes things like recently deposited items in a chest to be lost.

Alright. That's good to know.
I mainly brought this up to make people aware of it. I did also post the issue over on DE's issue tracker as well so they know as well. I don't think many people will run into this issue, as I only came across this because I threw BP into a modpack. I ran into the problem quite far into it. But if DE doesn't solve it, then atleast it can be added to a incompatibility list.

(Love BetterPortals by the way. nice seamlessly dimensional travel is awesome)

Dimensional Edibles completely bypasses the normal teleportation code which BP hooks into.
There's nothing I can really do about it except directly hooking into their code as well as the vanilla one. And unless they have a very good reason for duplicating the normal teleportation code (like e.g. Sponge had), I'm not up for that.

For reference:
BP's enhanced transition hook: https://github.com/Johni0702/BetterPortals/blob/a75586e8344f1d33b7170a2a9d7765255ae51a7f/src/transition/java/de/johni0702/minecraft/betterportals/impl/transition/mixin/MixinPlayerList.java
BP's fallback hook if enhanced transitions are disabled: https://github.com/Johni0702/BetterPortals/blob/a75586e8344f1d33b7170a2a9d7765255ae51a7f/src/view/java/de/johni0702/minecraft/view/impl/mixin/MixinPlayerList_NoSponge.java
DE's bypass: https://github.com/JackyyTV/DimensionalEdibles/blob/e5bbaa3805e6cd64ad439c980bb14dd844392d5c/src/main/java/jackyy/dimensionaledibles/util/TeleporterHandler.java#L30-L75