### Added

* Speed up `for x in xs -> …` in list & array comprehensions in certain scenarios. ([PR #16948](https://github.com/dotnet/fsharp/pull/16948))
* Lower integral ranges to fast loops in more cases and optimize list and array construction from ranges. ([PR #16650](https://github.com/dotnet/fsharp/pull/16650), [PR #16832](https://github.com/dotnet/fsharp/pull/16832))
* Support for nullable reference types ([PR #15181](https://github.com/dotnet/fsharp/pull/15181))
* Bidirectional F#/C# interop for 'unmanaged' constraint. ([PR #12154](https://github.com/dotnet/fsharp/pull/12154))
* Make `.Is*` discriminated union properties visible. ([Language suggestion #222](https://github.com/fsharp/fslang-suggestions/issues/222), [PR #16341](https://github.com/dotnet/fsharp/pull/16341))
* Allow returning bool instead of unit option for partial active patterns. ([Language suggestion #1041](https://github.com/fsharp/fslang-suggestions/issues/1041), [PR #16473](https://github.com/dotnet/fsharp/pull/16473))
* Allow access modifies to auto properties getters and setters ([Language suggestion #430](https://github.com/fsharp/fslang-suggestions/issues/430), [PR 16687](https://github.com/dotnet/fsharp/pull/16687), [PR 16861](https://github.com/dotnet/fsharp/pull/16861), [PR 17522](https://github.com/dotnet/fsharp/pull/17522))
* Allow #nowarn to support the FS prefix on error codes to disable warnings ([Issue #17206](https://github.com/dotnet/fsharp/issues/16447), [PR #17209](https://github.com/dotnet/fsharp/pull/17209))
* Allow ParsedHashDirectives to have argument types other than strings ([Issue #17240](https://github.com/dotnet/fsharp/issues/16447), [PR #17209](https://github.com/dotnet/fsharp/pull/17209))
* Support empty-bodied computation expressions. ([Language suggestion #1232](https://github.com/fsharp/fslang-suggestions/issues/1232), [PR #17352](https://github.com/dotnet/fsharp/pull/17352))
* Allow object expression without overrides. ([Language suggestion #632](https://github.com/fsharp/fslang-suggestions/issues/632), [PR #17387](https://github.com/dotnet/fsharp/pull/17387))
* Enable FSharp 9.0 Language Version ([Issue #17497](https://github.com/dotnet/fsharp/issues/17438)), [PR](https://github.com/dotnet/fsharp/pull/17500)))

### Fixed

* Allow extension methods without type attribute work for types from imported assemblies. ([PR #16368](https://github.com/dotnet/fsharp/pull/16368))
* Enforce AttributeTargets on let values and functions. ([PR #16692](https://github.com/dotnet/fsharp/pull/16692))
* Enforce AttributeTargets on union case declarations. ([PR #16764](https://github.com/dotnet/fsharp/pull/16764))
* Enforce AttributeTargets on implicit constructors. ([PR #16845](https://github.com/dotnet/fsharp/pull/16845/))
* Enforce AttributeTargets on structs and classes ([PR #16790](https://github.com/dotnet/fsharp/pull/16790))
* Ensure consistent interaction between ``#line` and `#nowarn` directives ([PR #17649](https://github.com/dotnet/fsharp/pull/17649))
* Revert EnforceAttributeTargets Feature. ([PR #18005](https://github.com/dotnet/fsharp/pull/18005))


### Changed

* Lower interpolated strings to string concatenation. ([PR #16556](https://github.com/dotnet/fsharp/pull/16556))
