e-mail from Andrea Hoffer on the OpenShift team:
I was trying to fix some build errors/warnings in the repo yesterday and came across a few files that have issues that I wasn't able to easily solve. I did my best to identify the best person to take a look at these files, but let me know if I should reach out to someone else.
 
I noted the files and issues in this spreadsheet: https://docs.google.com/spreadsheets/d/11ChZT47hVTTZR8Xc_pn9n5yvDCddwt8MIo605BzZwUA/edit#gid=0
 
The main two issues were:
 

• Multiple level one headings (= Heading) in a file. You can only have a single level one heading in a file. Anything else should either be broken out into a different module or assembly, or the TOC should be altered to get the desired leveling.
• Some assemblies have procedure content directly in them. Although this might not produce a build error, I came across them when tracking down other errors. The procedure content should be in a procedure module and included in the assembly.
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Branching the service mesh docs rearranging the modules and assemblies and introduced these errors.