VBA script to interact with FireFox browser
<p>I am trying to create VBA tool, that copy-paste some data from excel workbook to some internal company application, which we are using via browser. The program should "click" several buttons and checkboxes, and paste cells values into textboxes like this presented on following screens:</p>

<p><a href="https://i.stack.imgur.com/IiC2j.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/IiC2j.jpg" alt="SS1"></a></p>

<p><a href="https://i.stack.imgur.com/uByWQ.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/uByWQ.jpg" alt="SS2"></a></p>

<p><a href="https://i.stack.imgur.com/1yfNT.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1yfNT.jpg" alt="SC3"></a></p>

<p>Unfortunately, there are several restrictions:</p>

<ul>
<li>This site is not working on MS Internet Explorer. I can use it only by FireFox.</li>
<li>Thanks to security rules in may company, I am not able to install any software. So, I can't use Selenium (requires installing add-on), nor do this task with R or Python. </li>
<li>Clicking <code>Tab</code> key is not working, so I can't just <code>SendKeys "{TAB}"</code> multiple times. </li>
</ul>

<p>Have someone got any idea how I can resolve this?</p>