Add this CSS code to fix the double arrow problem like shown below:
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To add this css code, you just need to add this to the theme customizer area (Appearance > Customize > Additional CSS) And paste the code. Publish.
button.stp-control {
width: auto!important;
min-width: 25px;
}
Tutorial to add Additonal CSS code here : https://support.skyandstars.co/article/adding-additional-css-to-the-theme/