Products with variables are not visualizing their variable images

After installing WebP Express, the following problem appeared – products with variation do not have their variable images changed. Example: https://vitamag.bg/magazin/animal-parade/myltivitamini/gold-multi/, where we have three different flavors and when selecting each of them, the corresponding flavors were previously visualized, but after the activation of WebP Express yesterday, they no longer change the different images.

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