Hmm. While working on a webdriver test-case for an intervention here, I found that I can only make the card elements "disappear" if I trigger mousemove events while the cards' fading-in animation is happening. Then they vanish, and when I finally move my mouse again, they reappear. The problem doesn't happen at all if I use my physical keyboard to input letters instead of the mouse, and so I also had to have my webdriver test simulate some mouse-move events during the animations as well. So maybe this is a bug related to mousemoves during CSS animations? I think the page is also listening for mousemove events on the buttons, so perhaps that's related..
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Hmm. While working on a webdriver test-case for an intervention here, I found that I can only make the card elements "disappear" if I trigger mousemove events while the cards' fading-in animation is happening. Then they vanish, and when I finally move my mouse again, they reappear. The problem doesn't happen at all if I use my physical keyboard to input letters instead of the mouse, and so I also had to have my webdriver test simulate some mouse-move events during the animations as well. So maybe this is a bug related to mousemoves during CSS animations? I think the page is also listening for mousemove events on the buttons, so perhaps that's related.. Note that I also can't seem to reproduce the problem on my phone.