Hey Lulzbot folks,
Your gitlab release of v3.6.21 from 2 months ago has a small issue:
This release contains debian download links that provide 3.2.21, not 3.6.21
I think this is a simple typo as the Mac and Windows links do contain 3.6.21 and the prior release 3.6.20 provided consistent links for everything. Could you help us out and update that release with new links?
Also, I could not get your debian repo to work, are these instructions still valid? https://www.lulzbot.com/content/debian-cura-installation
Thanks for making awesome products,