This seems to happen more often now, but interestingly it only seems to happen on Linux. The last run was in https://github.com/mozilla/pdf.js/pull/13021#issuecomment-786012076. @calixteman Could you take a look at this to see if we can make the tests pass again?

The relevant log output is:

```
Failures:
1) Interaction in js-colors.pdf must changes colors
  Message:
[31m    In firefox: Expected 'rgba(0, 54, 255, 0.13)' to equal 'rgb(255, 0, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgba(0, 54, 255, 0.13)' to equal 'rgb(255, 0, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:661:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:667:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:676:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(0, 0, 255)' to equal 'rgb(255, 0, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(0, 0, 255)' to equal 'rgb(255, 0, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:661:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:667:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:676:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(0, 0, 255)' to equal 'rgb(255, 0, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(0, 0, 255)' to equal 'rgb(255, 0, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:661:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:667:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:676:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(0, 0, 255)' to equal 'rgb(255, 0, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(0, 0, 255)' to equal 'rgb(255, 0, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:661:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(255, 0, 0)' to equal 'rgb(0, 255, 0)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:667:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
  Message:
[31m    In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.[0m
  Stack:
    Error: In firefox: Expected 'rgb(0, 255, 0)' to equal 'rgb(0, 0, 255)'.
        at <Jasmine>
        at Promise.all.pages.map (/home/ubuntu/pdfjs/botio-files-pdfjs/private/e2b7f68c964756b/test/integration/scripting_spec.js:676:16)
        at process._tickCallback (internal/process/next_tick.js:68:7)
```
}
    await action();
    await page.waitForFunction(
      `document.querySelector("${selector.replace("\\", "\\\\")}").value !== ""`
    );
    return page.$eval(selector, el => el.value);
  }
  describe("in 160F-2019.pdf", () => {
    let pages;
    beforeAll(async () => {
      pages = await loadAndWait("160F-2019.pdf", "#\\34 16R");
    });
    afterAll(async () => {
      await closePages(pages);
    });
    it("must check that first text field has focus", async () => {
      await Promise.all(
        pages.map(async ([browserName, page]) => {
          await page.waitForFunction(
            "window.PDFViewerApplication.scriptingReady === true"
          );
          
          
          const id = await page.evaluate(
            () => window.document.activeElement.id
          );
          expect(id).withContext(`In ${browserName}`).toEqual("401R");
        })
      );
    });