Type: Bug

1. Create a JSON Schema file (schema file) with the json extension and the following contents.

{
    "$schema": "http://json-schema.org/draft-07/schema",
    "type": "object",
    "additionalProperties": false,
    "properties": {
        "$schema": {
          "type": "string"
        },
        "test": {"type": "boolean"}
    }
}

2. Create a second file (instance file) in the same folder with the json extension and the following contents.

{
    "$schema": "http://json-schema.org/draft-07/schema",
    "type": "object",
    "additionalProperties": false,
    "properties": {
        "$schema": {
          "type": "string"
        },
        "test": {"type": "boolean"}
    }
}

3. Note that there are no problems in the instance file.
4. Change the name of the property in the schema file from test to test1 and save.
5. Note that there is now a problem in the instance file without having to reload Visual Studio Code.

"Property test is not allowed."

6. Change the extension of the schema file and the reference to it in the instance file to json (instead of jsonc).
7. Change the name of the property in the schema file from test1 back to test.
8. Note that the problem in the instance file remains.

"Property test1 is not allowed."

9. Restart Visual Studio Code.
10. Note that there are no longer any problems in the instance file.

Visual Studio Code does appear to support JSON Schemas with the jsonc extension just like it does those with a json extension. Unlike schema files with the json extension though, those with the jsonc extension require a restart of Visual Studio Code to have changes relected in the validation of instance documents.

Note that this workaround also resulted in the schema changes being reflected.

https://stackoverflow.com/a/70175188/81595

VS Code version: Code 1.79.0 (b380da4, 2023-06-07T14:26:35.552Z)
OS version: Windows_NT x64 10.0.19045
Modes:

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