Gridsync's tahoe module currently contains a workaround/hack for the fact that, some years ago, Twisted's reactor.spawnProcess() did not correctly suppress "Command Prompt"/terminal windows on win32. @exarkun, however, has recently pointed out that this has been fixed upstream in Twisted and so, in the broader interest of reducing platform-specific hacks wherever possible in the codebase, Gridsync should use Twisted's reactor.spawnProcess() now that it has been fixed.