3.5. Comments
The hash symbol, or #, can be placed at the beginning of a line to add comments or to temporarily disable a configuration field. They are ignored by the configuration parser and will not affect the behavior of the registry. For example:
# ...
# FEATURE_UI_V2: true
# ...
In this example, the FEATURE_UI_V2 configuration is ignored by the parser, meaning that the option to use the v2 UI is disabled. Using the # symbol on a required configuration field results in failure for the registry to start.