RangeError during captureElememtScreenshot

[eilensm]

Hello,

I'm new to nightwatch and nightwatch-vrt and but finally managed to get a sensible setup and initial test running. We want to do some visual regression tests of a Vue.js app for Chrome, Firefox and IE.

Now, I get an error in my test for my firefox headless setup. For IE, Chrome (non-headless and headless) and Firefox (non-headless) it works.

I think it has to do with a negative y axis value for the selected element, as I was able to log (see the code)

describe("App page", () => {
  it("should compare screenshot to baseline", browser => {
    const elementSelector = "#app";
    browser
      .init()
      .getLocationInView(elementSelector, value => {
        console.log("value", value);
      })
      .assert.visible(elementSelector)
      .assert.screenshotIdenticalToBaseline(elementSelector, "app")
      .end();
  });
});

In the non-headless mode, y has the value 8, in headless mode, following is logged:
value { state: 'success', sessionId: null, value: { x: 8, y: -34.600006103515625 }, status: 0 }
Any idea???

Here is some additional information about my setup...

"npm/6.13.2 node/v12.13.1 win32 x64"
"nightwatch": "version": "1.3.1",
"nightwatch-vrt": "version": "0.2.10",
"geckodriver": "version": "1.19.1",
"selenium-server": "version": "3.141.59",

This is my nightwatch.conf.js, although I'm using a derived configuration for the vrt tests but there, I only adapt some pathes besides using the standards from the documentation...

module.exports = {
  test_settings: {
    selenium: {
      // Selenium Server is running locally and is managed by Nightwatch
      selenium: {
        start_process: true,
        port: 4444,
        server_path: require("selenium-server").path,
        cli_args: {
          "webdriver.gecko.driver": require("geckodriver").path,
          "webdriver.ie.driver": process.platform === "win32" ? require("iedriver").path : ""
        }
      }
    },
    // we need a selenium.firefox configuration, because plain webdriver does not support getLocationInView which is
    // called from nightwatch-vrt assertions... (also see https://github.com/nightwatchjs/nightwatch/issues/2275)
    "selenium.firefox": {
      extends: "selenium",
      desiredCapabilities: {
        browserName: "firefox"
      }
    },
    "selenium.firefox.headless": {
      extends: "selenium",
      desiredCapabilities: {
        browserName: "firefox",
        "moz:firefoxOptions": {
          args: ["--headless"]
        }
      }
    },
    "selenium.ie": {
      extends: "selenium",
      desiredCapabilities: {
        browserName: "internet explorer"
      }
    }
  }
};