I’m trying to create a Scratch Org from a modified project-scratch-def.json file in VSCode.
I can’t save the changes to the json file because I’m getting the error:
Unable to load schema from '/Users/myname/.vscode/extensions/salesforce.salesforcedx-vscode-core-61.12.0/node_modules/@salesforce/schemas/project-scratch-def.schema.json': ENOENT: no such file or directory, open '/Users/myname/.vscode/extensions/salesforce.salesforcedx-vscode-core-61.12.0/node_modules/@salesforce/schemas/project-scratch-def.schema.json'.

Here is the project-scratch-def.json

{
  "orgName": "myname company",
  "edition": "Developer",
  "features": ["EnableSetPasswordInApi"],
  "settings": {
    "lightningExperienceSettings": {
      "enableS1DesktopEnabled": true,
      "enableLightningPreviewPref": true
    },
    "mobileSettings": {
      "enableS1EncryptedStoragePref2": false
    }
  }
}

I have tried reinstalling node, reinstalling the Salesforce Extension Pack, reinstalling Salesforce CLI, rebooting the machine, reloading VSCode, recreating the project, deleting existing scratch orgs, and everything short of sacrificing a chicken in the full moonlight.

If I visit /Users/myname/.vscode/extensions/salesforce.salesforcedx-vscode-core-61.12.0/node_modules — there is no @salesforce directory there.