Failed to index to Algolia

I am trying to switch from the old gatsby-plugin-algolia-search plugin to the current version of gatsby-plugin-algolia but I always get the following error if there is any partial update to be done:

[Algolia] 2 queries to index
[Algolia] Running 1 query for index Posts...
[Algolia] Running 1 query for index Downloads...
[Algolia] Query resulted in a total of 4 results
[Algolia] Query resulted in a total of 12 results
success Generating image thumbnails - 0.038s - 5/5 131.32/s
[Algolia] Starting Partial updates...
error failed to index to Algolia

  ReferenceError: curObj is not defined

not finished onPostBuild - 0.513s

I am using WordPress to get my data. Here's my config:

gatsby-config.js

...
{
      resolve: `gatsby-plugin-algolia`,
      options: {
        appId: process.env.GATSBY_ALGOLIA_APP_ID,
        apiKey: process.env.ALGOLIA_ADMIN_KEY,
        indexName: process.env.GATSBY_ALGOLIA_POSTS_INDEX_NAME,
        queries: require('./src/utils/algoliaQueries'),
        chunkSize: 10000,
        enablePartialUpdates: true,
      },
    },
...

./src/utils/algoliaQueries.js

const postsQuery = `{
  allWpPost(
      filter: { status: { eq: "publish" } }
      sort: { fields: date, order: DESC }
    ) {
      nodes {
        objectID: id
        title
        slug
        excerpt
        date_timestamp: date
        categories {
          nodes {
            name
          }
        }
        tags {
          nodes {
            slug
            name
          }
        }
        featuredImage {
          node {
            altText
            localFile {
              childImageSharp {
                fluid(maxWidth: 390, quality:  90) {
                  base64
                  aspectRatio
                  src
                  srcSet
                  sizes
                }
              }
            }
          }
        }
        author {
          node {
            slug
            name
          }
        }
      }
    }
  }
`;

const downloadsQuery = `{
  allWpDownload(
      filter: { status: { eq: "publish" } }
      sort: { fields: date, order: DESC }
    ) {
      nodes {
        objectID: id
        title
        slug
        downloadFields {
          type
          sourceLink
        }
        date_timestamp: date
        categories {
          nodes {
            name
          }
        }
        featuredImage {
          node {
            altText
            localFile {
              childImageSharp {
                fluid(maxWidth: 390) {
                  base64
                  aspectRatio
                  src
                  srcSet
                  sizes
                }
              }
            }
          }
        }
      }
    }
  }
`;

const flattenPost = (arr) =>
  arr.map(({ excerpt, date_timestamp, ...rest }) => ({
    excerpt: excerpt.replace(/(<([^>]+)>)/gi, ''),
    date_timestamp: parseInt(
      (new Date(date_timestamp).getTime() / 1000).toFixed(0),
      10
    ),
    ...rest,
  }));

const flattenDownload = (arr) =>
  arr.map(({ date_timestamp, ...rest }) => ({
    date_timestamp: parseInt(
      (new Date(date_timestamp).getTime() / 1000).toFixed(0),
      10
    ),
    ...rest,
  }));

const queries = [
  {
    query: postsQuery,
    transformer: ({ data }) => flattenPost(data.allWpPost.nodes),
    indexName: process.env.GATSBY_ALGOLIA_POSTS_INDEX_NAME,
    settings: {
      attributesToSnippet: [`excerpt:20`],
    },
  },
  {
    query: downloadsQuery,
    transformer: ({ data }) => flattenDownload(data.allWpDownload.nodes),
    indexName: process.env.GATSBY_ALGOLIA_DOWNLOADS_INDEX_NAME,
  },
];

module.exports = queries;

If there is no data to be updated, everything goes well. I haven't found anything about the ReferenceError: curObj is not defined that could be helpful. Did I miss any config setting?

algolia / gatsby-plugin-algolia

Failed to index to Algolia #108