package.json: Remove the file pattern from the eslint script.

eslint.config.(m)js: Create the eslint.config.mjs file. You can also create a eslint.config.js if the package is already ESM package.

Write the following content into the file, using the corresponding eslint-config package

import { createFrontendEslintConfig } from "@coremedia/eslint-config-frontend";

          export default createFrontendEslintConfig();

For more fine granular control over folders that should be linted you can utilize the options parameter of createEslintConfig, for example:

import { createFrontendEslintConfig } from "@coremedia/eslint-config-frontend";

export default createFrontendEslintConfig({ sourceFolders: ["src", "my-src"] });

.elsintrc: In case you do not have made any adjustments you can delete the .eslintrc file. Otherwise, you need to migrate the changes to v9 (Migrate to v9.x - ESLINT ) and add them to the eslint.config.(m)js file which can be done like this:

import { createEslintConfig } from "@coremedia/studio-client.eslint-config";
import { defineConfig, globalIgnores } from "eslint/config";

export default defineConfig([
  createEslintConfig(),
  {
    // your custom eslint config
  },
]);

Run the linter and fix reported problems.