Linux Mint 19.1 'Tessa' has been made available for public release. An upgrade path for those on Mint 19 is planned and will become available very soon but it hasn't been detailed just yet.
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The Linux Mint project has pushed the betas for the upcoming Linux Mint 19.1 release. There are still bugs lingering so if you run into any, be sure to report them so they can be fixed.
Clement Lefebvre, head of the Linux Mint project, has announced that Linux Mint 19.1 will be released in time for Christmas. All of the spins and upgrade paths will be made available together.
The Linux Mint team has shared some updates pertaining to its software that we will see in Linux Mint 19.1, due later this year. There are lots of refinements and a speed boost for the file manager.
Linux Mint 19.1 has been given the codename 'Tessa'. The upcoming release being worked on right now will be ready for release in November or December later this year. It will be supported until 2023.