How to load custom gems to the OpenStudio application?

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I want to use NRCan's version of openstudio-standards in the OpenStudio application. While there is documentation on loading a custom gemfile for the CLI (https://nrel.github.io/OpenStudio-use...), I am not able to find one for the application itself. I tried adding the gemfile path to GEM_PATH or GEM_HOME in the environment variables, but that didn't work for me. I might be doing it incorrectly, please guide me on this issue.