false is returned from
JUCEApplication::moreThanOneInstanceAllowed and you attempt to bring your main window to the foreground by calling
toFront in response to
JUCEApplication::anotherInstanceStarted, the window’s task bar icon simply flashes.
In Windows, this is by design. However, calling
JUCEApplicationBase::MultipleInstanceHandler::sendCommandLineToPreexistingInstance allows the existing instance’s call of
toFront to succeed.