InjectAxe fails on cy.readFile error when using Cypress Webpack Preprocessor

I'm seeing the following error when running cy.injectAxe in my Cypress tests:

Timed out retrying after 4000ms: cy.readFile("0764") failed because the file does not exist at the following path:

/home/megan/voicethread/code/frontend/wizard/0764

Because this error occurred during a before each hook we are skipping the remaining tests in the current suite

node_modules/cypress-axe/dist/index.js:16:8
  14 | exports.configureAxe = exports.injectAxe = void 0;
  15 | exports.injectAxe = function () {
> 16 |     cy.readFile(require.resolve('axe-core/axe.min.js')).then(function (source) {
     |        ^
  17 |         return cy.window({ log: false }).then(function (window) {
  18 |             window.eval(source);
  19 |         }); 

require.resolve('axe-core/axe.min.js') seems to evaluate to "0764" instead of the intended JS.

This issue seems to be connected to Cypress's Webpack Preprocessor, which I'm using to handle importing files with absolute path aliases.

const webpack = require('@cypress/webpack-preprocessor')

module.exports = (on, config) => {
  on('file:preprocessor', webpack({
    webpackOptions: require('@vue/cli-service/webpack.config'),
    watchOptions: {},

    // Add the ability to use aliases like @shared
    resolve: {
      alias: require('../../../../aliases.config').webpack
    }
  }))

  return Object.assign({}, config, {
    fixturesFolder: 'tests/e2e/fixtures',
    integrationFolder: 'tests/e2e/specs',
    screenshotsFolder: 'tests/e2e/screenshots',
    videosFolder: 'tests/e2e/videos',
    supportFile: 'tests/e2e/support/index.js'
  })
}

When I remove the on('file:preprocessor') listener from my plugins.js, file, the cy.injectAxe command succeeds.

Node version: 12.13.1
Cypress version: 6.3.0
@cypress/webpack-preprocessor version: 5.5.0

Reproduce cy.injectAxe with the @cypress/webpack-preprocessor listener in plugins.js, using the versions and configuration shown. Start at node_modules/cypress-axe/dist/index.js:16 and compare behavior with the listener removed. Done means cy.injectAxe can read axe-core and the Cypress tests proceed successfully with the preprocessor enabled.