> Pretty good, https://ionide.io

It pains me to admit it because I really like F# but, with due respect to the developers, Ionide and its related projects are the most unstable toolchain I've ever used.

Spend half a day reloading the editor because the extension keeps hanging on non-trivial MSBuild only to discover that the formatter has truncated in half one of the files you worked on due to a soundness bug. (OCaml's editor support, in contrast, is quite stable.)

Rider is the best editing experience I've had with F#, by far.