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[beardgans]

Hi everyone! And thank you for this awesome project!

I found this feature very useful in the GitHub CLI application and npm.

I think it'll be useful for users who install mdBook using cargo. And this will let them know that a new version is available and it's time to update.

Ready-made crates to do that:

• https://github.com/mgrachev/update-informer
• https://github.com/tarikeshaq/update-notifier

[mgeisler]

I think it'll be useful for users who install mdBook using cargo. And this will let them know that a new version is available and it's time to update.

I ran into a tool which does this just today: I noticed it because there was a lag at the end of the help output.

I would not bother with this: it adds extra complexity and it changes mdbook from being an offline tool to a tool which sometimes contacts "something" on the internet.