Steps to reproduce: - Create a new project with create-rescript-app ("basic" template is sufficient) - Build the project - Open the editor - Introduce an error (e.g. "Console.log" -> "Cnsole.log") => the error is underlined correctly in the editor - Undo the error - Clean and rebuild the project, keeping the editor open - Reintroduce the error => it is not shown in the editor this time