`LetsConfusion` flags "let's you" as a redundnat pronoun rather than a mistke for "lets you"

[hippietrail]

Current macOS Finder let's you name files with a slash in them,

But actually it does offer both corrections "let's" and "lets you". So either the message needs to be improved, or the context might be able to be analyzed to offer only the right suggestion or a varying message depending on the specific case.