View the original community article here
Last tested: Mar 17, 2020
There's currently no way to hide folders in the IDE, but a workaround is to "tag" the current version on github, and then delete the files, then if you want to see the old files you could navigate to the tag.
https://stackoverflow.com/questions/18216991/create-a-tag-in-a-github-repository
Once you have a tag, called for example "last-rev-with-old-lookml" then you can look at the files a https://github.com/ACCOUNT/REPO/tree/last-rev-with-old-lookml so you could bookmark that and keep it as a reference for example.
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