Hello,

When you set a custom size of an image, Elementor resizes a raster image using its own compression settings, which we can’t control via WordPress theme. There is several solutions of this issue.

1. Use vector images for icons, which will always look sharp and do not have problems with compression artifacts that raster images have.

2. If you want to use raster images, we recommend you to change image file dimensions in image editor to the desired values, save it without compression and upload to the infobox element using Full image size option (https://prnt.sc/1falx9p).

Kind Regards