It also looks to me like the same issue is happening on your coming soon demo here – https://kriesi.at/themes/enfold-coming-soon/
I can’t see the countdown timer. (I am on Chrome on Windows btw). See the opacity on this element – av-countdown-timer
I am having this same issue.
It looks like an issue with the opacity on animated blocks – it looks like the opacity doesn’t change to 1 for the animations to render. I guess this is an issue with the js but I have put a temporary hacky fix in the css to force an opacity of 1 on the gallery and slider for my site. This was also happening on a timeline animation and a couple other blocks.
EXAMPLE: You can see my hacky fix on this page – https://www.jmwingchun.com/about/our-lineage/ I have given the list item in the timeline an opacity of 1 through the wordpress theme editing tools which is fine for now but I have no idea what else it might break down the line.
The gallery wasn’t displaying on this page either: https://www.jmwingchun.com/about/gallery/
A couple of other blocks could be fixed by simply switching off the animation, but these ones needed this css to rectify it.
I hope that helps.
This is WP version 5.6.1, Enfold Version: 4.5.5, php version 7.3.23
I don’t know exactly when it started but it was first reported to me on the 7th January by my client who uses his site regularly.