V12 Documentation - Compatibility Removals

[aaclayton]

Important

None of the following changes are new to Version 12, but a large number of breaking changes made in V9 or V10 have reached the end of their compatibility period. The removal of compatibility for the legacy behavior can cause code in V12 to break that was working in V11 if it has not yet been migrated. These changes will be introduced in Version 12 Prototype 1. Please read the issue carefully and join the discussion if you have any questions, suggestions, or concerns.

Hello community! We are making significant progress on Version 12 development and are getting to the point where we are starting to have a clear picture of what changes Version 12 includes. This discussion deals specifically with the removal of compatibility layers that were in place since V9 or V10 that kept certain old behaviors working. Please see a comprenehsive list of the removed behaviors in:

• Finalize breaking changes and deprecations from V10 and earlier which have reached the end of their compatibility period #10164

Let's Discuss!

We are sharing this information in advance of V12 Prototype 1, which is expected in early December, so that you can provide early feedback and plan ahead for changes you will want to investigate or test in your own systems and modules. We still have plenty of time to make further changes or to adjust our approach if anything described in this issue raises concern for you, so we are beginning this discussion early and will keep this thread open for discussion and feedback until the end of the V12 API Development phase.

You may also discuss this change in Discord in the V12 Compatibility Removals thread: https://discord.com/channels/170995199584108546/1171504255849484370

Frequently Asked Questions

Is this a breaking change?

Yes, because some code that was "working" (albeit with warnings) in v11 no longer will work in v12. The changes described here are not new to v12, however. These changes were made in v9 or v10 with a provided compatibility period until version 12 at which point the compatibility layers are being removed.