TuxGuitar has been released in version 2.1.0.

TuxGuitar is a cross-platform editor for guitar tablature that lets you create, edit and play multitrack scores, including import of Guitar Pro files.

The packages on the release page are not officially signed, and TuxGuitar has used a new file format since version 2.0.0 that older versions can no longer read.

The packages available here are not officially signed. To install them, you must temporarily disable the digital signature verification of your operating system (called “disable Gatekeeper” on macOS, “allow installation from unknown sources” on Windows, “Sideloading” on Android).

TuxGuitar versions 2.0.0 and later use a new file format which cannot be read by older versions. You can still export your tablatures in the old format.

Source: GitHub