Docs with conda options not being build because: Invalid "conda.file": file not found

[marimeireles]

Details

• Build URL (if applicable): https://readthedocs.org/projects/ipycytoscape/builds/12028391/
• Read the Docs username (if applicable): marimeireles

Expected Result

Docs build using conda to create an environment.

Actual Result

Docs don't build and I get the following:

Problem in your project's configuration. Invalid "conda.file": file not found

I tried to follow the docs and projects that use conda to build their envs and there is no difference between my files and theirs. See:
readthedocs.yaml: https://github.com/QuantStack/ipycytoscape/blob/master/readthedocs.yml
doc envs: https://github.com/QuantStack/ipycytoscape/blob/master/docs/environment.yml

I'm trying it as an alternative to pip since it's causing me a few problems #7520.

Any idea of what might be wrong?
Thanks a lot!

[stsewd]

Hi, you are missing the version of the config file, see https://docs.readthedocs.io/en/stable/config-file/v2.html#conda