Free Alternative to Help Scout Help Desk

Just received "Phasing out the Help Scout Free plan" email from Help Scout:

"For a lot of reasons, we haven’t been successful in maintaining a “freemium” version of the product that makes sense for our business, and have decided to phase out all Free plans over the next six months."

It means that now many companies need to find a free open source alternative to Help Scout. There is one project on GitHub called FreeScout and devoted to development of the free Help Scout alternative. But it looks like they are just starting and who knows how much time it will take for them to release the app.

So if anybody knows any free help desk systems out there, please share them in comments.

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Always yours,
Hi-Tech Yoga