problems when on sale

When I use the booster product addons plugin to add options to my products, it does strange things when I put a product on sale. Instead of showing the product regular price crossed out, it shows the sale price crossed out, with the sale price next to it. So basically it looks like I have a sale price that is the same price as the regular price. You will see the regular price for just a split second, then it adjusts to the sale price.

If I disable booster product addons, it works fine.

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