issue_comments: 260030024

The error is visible here the latest build logs are available here thanks!

Thanks @fmaussion I can see that there are multiple conda install commands the the subsequent ones change the env. For example:

``` conda install --yes --name latest sphinx==1.3.5 Pygments==2.1.1 docutils==0.12 mock pillow==3.0.0 sphinx_rtd_theme==0.1.7 alabaster>=0.7,<0.8,!=0.7.5

Fetching package metadata: .... Solving package specifications: .........

Package plan for installation in environment /home/docs/checkouts/readthedocs.org/user_builds/xray/conda/latest:

The following NEW packages will be INSTALLED:

jbig:             2.1-0       
sphinx_rtd_theme: 0.1.7-py27_0

The following packages will be DOWNGRADED:

freetype:         2.6.3-1      --> 2.5.5-1     
jpeg:             9b-0         --> 8d-2        
libtiff:          4.0.6-7      --> 4.0.6-2     
pillow:           3.4.2-py27_0 --> 3.0.0-py27_1
pygments:         2.1.3-py27_1 --> 2.1.1-py27_0
sphinx:           1.4.8-py27_0 --> 1.3.5-py27_0
tk:               8.5.19-0     --> 8.5.18-0

```

That jpeg change is not desirable!

I also cannot see the full log from conda env create --name latest --file /home/docs/checkouts/readthedocs.org/user_builds/xray/checkouts/latest/doc/environment.yml.

It's the same environment, I'm literally typing "git checkout master" or "git checkout v0.8.2" in my xarray-dev conda environment (on Python 3.5)

I am not sure it is due to the change I mention above. I will make a few experiments and report back.