ElementNotVisibleException when use headless Chrome browser

Question

When I run test script in headless mode chrome browser, element link is not visible, is not able to do linkElement.click(). in head mode is everything OK. All other info are in stacktrace. Anyone knows what to do, please?

StackTrace:

ERROR occurred: Message: element not visible
(Session info: headless chrome=60.0.3112.90)
(Driver info: chromedriver=2.31.488763 (092de99f48a300323ecf8c2a4e2e7cab51de5ba8),platform=Windows NT 6.1.7601 SP1 x86_64)
Traceback (most recent call last):
File "C:\nik-x.py", line 148, in main
func(nik)
File "C:\lib\support.py", line 121, in wrapper
raise ret
File "C:\lib\support.py", line 108, in newFunc
res[0] = func(*args, **kwargs)
File "C:\testcases\nik-1003.py", line 37, in testcase
i.click()
File "C:\Python36\lib\site-packages\selenium\webdriver\remote\webelement.py", line 7
7, in click
self._execute(Command.CLICK_ELEMENT)
File "C:\Python36\lib\site-packages\selenium\webdriver\remote\webelement.py", line 4
93, in _execute
return self._parent.execute(command, params)
File "C:\Python36\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 25
6, in execute
self.error_handler.check_response(response)
File "C:\Python36\lib\site-packages\selenium\webdriver\remote\errorhandler.py", line
194, in check_response
raise exception_class(message, screen, stacktrace)
selenium.common.exceptions.ElementNotVisibleException: Message: element not visible
(Session info: headless chrome=60.0.3112.90)
(Driver info: chromedriver=2.31.488763 (092de99f48a300323ecf8c2a4e2e7cab51de5ba8),platform=Windows NT 6.1.7601 SP1 x86_64)

Here is my piece of code:
icons = nik.elementLeftmenuSportIcons() for i in icons[:-1]: try: i.click()

HTML from testing page: <a href="#" class="default b_futbal gaPageEventElement" data-ga-cat="Sporty" data-ga-action="futbal"> <span class="left-menu-only-large-res">Futbal</span> </a>

Answer 1

Adding this here as a reference for the future, as I faced the same problem. The problem was that the website I was trying to access banned my IP and I was using PROXY_TOOL to access it.

In Full mode, it worked fine, but in Headless mode, it showed that it was unable to find an element. So, I took a screenshot with this function before it showed that it was unable to find an element. (Python 3.9.5)

    def get_screenshot(self, filename):
    screenshot_bytes = self.driver.get_screenshot_as_png()
    with open(filename, "wb") as file:
        file.write(screenshot_bytes)

After saving the screenshot I saw that site was giving an IP blocked error. So, I used PROXY_IP="127.0.0.1", PROXY_PORT=9666 as arguments. On which PROXY_TOOL was serving the proxy access. And it worked.

options.add_argument("--proxy-server=socks5://" + str(PROXY_IP) + ":" + str(PROXY_PORT))

Use the screenshot function to see what is visible on the website in headless mode. See what kind of problem there is if the element is not visible use window size adjustment to make it visible. And adjust according. This might not be the right answer but it is directed to the same problem.

Answer 2

I think the problem is, that the Element is really not visible in the default viewbox (600x800) of Headless Chrome.

The window size of the Headless Browser must be set as a Argument when starting chrome. I'm using javascript (I think the API looks similar under python):

var Options = require('selenium-webdriver/chrome').Options;
var options = new Options();
options.addArguments('headless');
options.addArguments('disable-gpu');
options.addArguments('window-size=1200,1100');

browser = builder.forBrowser('chrome').setChromeOptions(options).build();

Additional Info

I'm setup up the window size also by webdriver with browser.manage().window().setSize(1200,1100); But this command is not sufficient in headless chrome. In the non headless variant this is working.