Fix InvalidCharacterError

✅ Solution

The "InvalidCharacterError" in Angular commonly arises when attempting to use characters in CSS class names (or other string contexts like configuration values used for class names) that are not permitted by CSS syntax rules. This often includes characters beyond basic alphanumeric and hyphen/underscore. To fix it, ensure your class names (or any values used directly as CSS classes) adhere to valid CSS syntax, typically by restricting them to alphanumeric characters, hyphens, and underscores; alternatively, properly escape invalid characters. You might need to refactor your component styles and configuration logic to generate or consume CSS-compliant class names.