In my react app I am using react-quill for the text editor and on the backend sanitize-html with JOI for the validation. In the text editor leaving empty lines results to this: <p><br></p>. sanitize-html does not allow ‘br’ tags by default, but no matter the option it will not allow the tag.

My code is

const extension = (joi) => ({
  type: 'string',
  base: joi.string(),
  messages: {
    'string.escapeHTML': '{{#label}} must not include HTML tags',
  },
  rules: {
    escapeHTML: {
      validate(value, helpers) {
        const clean = sanitizeHtml(value, {
          allowedClasses: {
            '*': [
              'ql-align-right',
              'ql-align-center',
              'ql-align-justify',
              'ql-code-block',
              'ql-code-block-container',
              'ql-syntax',
              'ql-direction-rtl',
              'ql-font-serif',
              'ql-font-monospace',
              'ql-formula',
              'ql-indent-1',
              'ql-indent-2',
              'ql-indent-3',
              'ql-indent-4',
              'ql-indent-5',
              'ql-indent-6',
              'ql-indent-7',
              'ql-indent-8',
              'ql-size-small',
              'ql-size-large',
              'ql-size-huge',
            ],
          },
        });
        if (clean != value)
          return helpers.error('string.escapeHTML', { value });
        return clean;
      },
    },
  },
});

I have tried

const clean = sanitizeHtml(value, {
  allowedTags: sanitizeHtml.defaults.allowedTags.concat([ 'br' ])
});

and even

allowedTags: false,
allowedAttributes: false

but still it will not allow the br tag.