I’m happy to present you the first release candidate of the 1.3.9 release!

The changelog is once again on the lengthy side thanks to the maintenance releases now being spread apart a bit further. Don’t let that scare you though 😉

Here are some highlights from the release notes:

  • A very annoying race condition causing OctoPrint to get stuck in “Cancelling” or “Pausing” state was identified and fixed. See also this FAQ entry which outlines the workarounds for this issue if you didn’t yet come across them.
  • An observed incompatibility with pip versions 10 and after that caused issues with plugin installation/uninstallation was also identified and fixed (see here for details).
  • Added support for plugins to override GCODE analysis provider and live print time estimation with their own implementations through two new hooks octoprint.filemanager.analysis.factory and octoprint.printer.estimation.factory. Feel free to go nuts with this.
  • Allowed more granular control over components to be upgraded through the software update plugin in its settings dialog. Instead of performing an “all-or-nothing” update, you may now apply each update individually.
  • Added detection for more unsafe firmwares to the bundled Printer Safety Plugin:
    • Anycubic Mega
    • Malyan M200
    • CR-10S
    • all Repetier firmware versions prior to 0.92
    • any firmware that reports the THERMAL_PROTECTION capability as disabled to thermal protection warning (see also MarlinFirmware/Marlin#10465)
  • Added a new bundled plugin “Action Command Prompt support” that allows printer firmware to trigger confirmation/decision dialogs in OctoPrint (e.g. for filament swaps).
  • The bundled web server Tornado was updated to a newer version to work around issues with client IP logging and other things. This also led to the discovery of a heads-up for anyone running OctoPrint behind NGINX - please see the release notes for details on this.
  • As announced with the release of OctoPrint 1.3.6, the legacy plugin bundling flag has now been removed again. Plugin authors, please make sure to check your plugins if you haven’t done that so far!
  • And of course there were also quite a number of bugs fixed reported for earlier versions, e.g. the logged in user switching to _api if the general API key was used to access the API in the same browser instance, inconsistencies in the port and baud rate lists between connection and settings dialog, a race condition in resend handling in case of missing oks, plus various fixes of typos and grammar in the documentation.

You can find the full changelog and release notes as usual on Github.

Special thanks to everyone who contributed to this release candidate, especially @benlye, @dadosch, @dforsi, @ganey, @malnvenshorn, @ntoff, @tedder and @vitormhenrique for their PRs.

If you are tracking the “Maintenance RC” release channel, you should soon get an update notification just like you are used to from stable releases.

If you want to help test this release candidate and aren’t yet tracking the “Maintenance RCs” release channel, you can find information on how to switch in this guide (also linked below).

If you are not interested in helping to test release candidates, just ignore this post, 1.3.9 stable will hit your instance via the usual way once reports indicate that it’s ready 😊

Please provide feedback on this RC. For general feedback you can use this ticket on the tracker. The information that everything works fine for you is also valuable feedback 😄 For bug reports please follow “How to file a bug report”.

Depending on how the feedback for this release candidate turns out, I’ll either look into releasing 1.3.9 or fix any observed regressions and push out a new release candidate ASAP.