Investigate how CSS animations change some properties

[Jym77]

It seems that properties whose values are changed by a CSS animation still keep their initially declared value (but compute to the result of the animation). When there is an animation onload (e.g. fading in the content), this seems to result in Alfa only seeing the pre-animated values and incorrectly assessing the page (e.g. thing that the content is still invisible and hasn't fade in).

<style>
  @keyframes keyframes1 {
    from { visibility: hidden; }
    to { visibility: visible; }
  }
  .class1 {
    visibility: hidden; 
    animation: keyframes1 1s;
    animation-fill-mode: forwards;
  }
</style>

 <div class="class1">This shows after animation but is incorrectly considered as invisible by Alfa. </div>

Need to understand what really happens and especially whether scraping the page after a delay would solve the problem.
It may be that Alfa will need to understand animations.

• Follow up on DEV-14431
• Follow up on II-7978