It should but apparently Sweet Home 3D with Java 11 doesn't perform this removal under Windows anymore
I'll try to check what's going on and fix it in the next version. Meanwhile, if you don't clear the work directory yourself, only subfolders of work directory older than a week will be cleared 10 minutes after program launch. Sorry for the inconvenience this regression may cause you and thanks for reporting it.
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Emmanuel Puybaret, Sweet Home 3D creator
