Which APIs and features will be unavailable in MSFS2024?

Per the FAQ, some addons will not work in MFS2024. We’d like to understand
which APIs are risky and will not be supported in the future. I understand the
next simulator is on the horizon but since all addons are not going to be
compatible, we’d like to know what to stay away from and avoid bad strategic
decisions over the next 6-18 months while waiting for FS2024.
https://www.flightsimulator.com/microsoft-flight-simulator-2024-faq/ > With
very few exceptions, virtually all add-ons that work in Microsoft Flight
Simulator (2020) today will function in Microsoft Flight Simulator 2024.

We need know Asap , we need know which features will be included. It seems
that msfs 2024 is a news flight sim but for developers not so much differences
…. The thing that is important (like you wrote) is go deep in. Dev model and
understand if our features we have in our announced and mostly in unannounced
addons overlapping main msfs 2024 new features …. It is crucial for our
business. I hope Asobo and Microsoft start a closed alpha asap for us
developers … otherwise we risk to go with strategic decision that could be a
wrong decision … Fabio

Pretty sure one of them is the UI system: Asobo has 20+ open job postings for
MSFS, some of them being UI specific, such as: “We are opening a Lead UI
Programmer position as part of the implementation of a new UI tech on the
Microsoft Flight Simulator project.” Asobo Studio – Lead UI Programmer H/F
(Flight
Sim)

I could be wrong, but I suspect they are ditching Coherent GT and developing
their own modern C++ UI engine, and then the current UI framework system will
sit on top of that. So a new UI engine, improved UI framework but same
interfaces to feed UI/Gauges etc, with a spiffy new MSFS 2024 front end
design. Logically, if they are saying “most” addons will migrate aok, then by
implication the current Gauge frameworks, JS/HTML, WASM API’s etc are expected
to be the same, but a revamped UI engine will then give them more capability.
Ditto for other components, such as some of the missing API’s we’ve all asked
about. It makes sense to do this as a new sim, as you are swapping out the
engine(s) but keeping the interfaces (and improving them with expanded
capability) the same to endure compatibility between the two versions, more or
less. Will see!