Top level README is way out of date.
Brief summary of bug
It refers to a spreadsheet that hasn't been updated since 2018 or so.
General bug information
CESM version you are using: [Output of git describe]
Machine you are using: [Fill this in]
Have you modified the code? (If so, please point us to you changes.): [Yes / No]
Details of bug
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Steps to reproduce the problem. Include externals description file(s) and link to public repository
[Fill this in with anything relevant that you haven't already noted; if there is nothing to add, delete this section.]
Screen output or log file showing the error message and context
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The link under 1.3 is also broken: http://esmci.github.io/cime/users_guide/porting-cime.html
It should point here: http://esmci.github.io/cime/versions/master/html/users_guide/porting-cime.html