v1.21.0 breaks jQuery slider

Hi, since updating from v1.20.1 to v1.21.0 the jQuery sliders on my website have broken. Images just aren’t being displayed on v1.21.0. They are loading in the DOM, just not showing.

Everything was working fine in v1.20.1. Here’s a quick video explanation that shows the issue – https://www.dropbox.com/s/so55276xeu69snd/coblocks%20slider%20bug%201.21.0.mp4?dl=0

Looks like a bug. Please advise, thanks.

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