I'm using a basic template - I've written some code in the F# script file, select the whole file, and hit alt+enter. Sometimes, it opens FSI as expected. However, today it started opening zsh:

Using >fsi: Send Selection from the command palette does the same thing.
I'm using a mac with macOS Sierra.
It's probably same bug as mentioned by @kirill-gerasimenko in https://github.com/ionide/ionide-vscode-fsharp/issues/161#issuecomment-249674690.
I've got powershell as a terminal, and with my custom profile it takes ~4-6 seconds to just load. So 1.5 seconds is not enough.
I'll be probably able to fix it when new stable version of Code will be released - https://github.com/Microsoft/vscode/issues/547#issuecomment-249707904
Sounds good!
Fixed in 2.6.8
馃槃
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It's probably same bug as mentioned by @kirill-gerasimenko in https://github.com/ionide/ionide-vscode-fsharp/issues/161#issuecomment-249674690.
I'll be probably able to fix it when new stable version of Code will be released - https://github.com/Microsoft/vscode/issues/547#issuecomment-249707904