As noted in my recent article on the promotion of the Lab’s Alex Ivy 64-bit viewer to release status, there is currently no official 64-bit support for Linux at this time.
It is hoped with will change: the Lab is establishing a viewer build environment to build a Debian version of the viewer with the various specialist libraries required by the various flavours of Linux. The hope being that this, with contributions from the open-source community, will provide a means for the Linux flavour of the viewer to continue, with viewer developers adding the specific libraries they may need as required.
It’s not clear how long it will take for all of this to mature, and for a Debian version of the viewer to appear. In the meantime, it means that as the Lab baseline their viewer build process on Alex Ivy, and existing project and release candidate viewers are updated to the Alex Ivy code, they will cease having Linux versions. This can already be seen with the 360 snapshot viewer, the project render viewer, and the Nalewka RC at the time of writing (versions 188.8.131.526743, 184.108.40.2061873, and 220.127.116.111871 respectively), none of which have a Linux flavour of the viewer. As the remaining project and RC viewers currently in the pipeline are updated with the new code case, they will also be without a Linux version for the time being.
To help compensate for this, on Thursday, January 18th, 2018, the Lab release the Linux Spur release candidate viewer, version 18.104.22.1689906. Dated November 17th, 2017, this viewer is in fact the Martini RC viewer which was promoted to release status on November 29th, 2017 – the latest viewer to be promoted to release status prior to Alex Ivy being promoted.
While it is not explicitly stated in the release notes, it is unlikely this version of the viewer will be updated with bug fixes, updates, etc., but will be offered until such time as a Linux viewer using the 64-bit libraries is made available. As such, it may offer a means for SL viewer users on Linux wishing to continue using that viewer, rather than a TPV flavour of Linux.
Obviously, those TPVs providing their own Linux flavour of the viewer are free to continue to do so.