I'm confused by the tags on docker hub

[barbudor]

Hello
I would like to test octoprint as a docker container but I'm confused with the tags I can see on docker hub.

The readme say:

The octoprint/octoprint image uses semantic versioning, but the tags for octoprint/octoprint follow the version of octoprint contained in the image

But apart from canary & canary-minimal, all other tags do not matches the releases on github:
Undefined, 76.0.0, 5512.0.0, 6.0.0 ...
I can't seem to find any 3.1.0 for example

Could you please confirm what those tags are ?

Thanks

[barbudor]

Answering - partially - to myself.

I found the tags latest & 1.5.2 which, now I understand includes Octoprint 1.5.2 (latest).

But what are those strange numbers ? 76.0.0 5512.0.0 6.0.0 ?
I can't find any matching releases or tags in Octoprint ?

thanks