Comment after then keyword gets removed

[theimowski]

Issue created from fantomas-ui

Please describe here fantomas problem you encountered

Code

if true then // comment
    ()

Result

if true then ()

Options

Fantomas Next - 3.3.0-3/18/2020

Name	Value
IndentOnTryWith	false
IndentSpaceNum	4
KeepNewlineAfter	false
MaxIfThenElseShortWidth	40
PageWidth	120
ReorderOpenDeclaration	false
SemicolonAtEndOfLine	false
SpaceAfterComma	true
SpaceAfterSemicolon	true
SpaceAroundDelimiter	true
SpaceBeforeClassConstructor	false
SpaceBeforeColon	false
SpaceBeforeLowercaseInvocation	true
SpaceBeforeMember	false
SpaceBeforeParameter	true
SpaceBeforeSemicolon	false
SpaceBeforeUppercaseInvocation	false
StrictMode	false