If you want to hide the following overlay message on SlideShare presentations:

You are reading a preview.
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...you can use the following custom filter :

www.slideshare.net##DIV[class="limit-overlay"]
fr.slideshare.net##DIV[class="limit-overlay"]

The custom filter I use:

www.artstation.com##SUPPORT-ARTSTATION-BLOCK
www.artstation.com##DIV[class="home-blocks"]
www.artstation.com##SECTION[class="home-featured home-featured-jobs"]
www.artstation.com##DIV[class="home-featured"]
www.artstation.com##DIV[class="gallery-marketplace-inner"]
www.artstation.com##FOOTER[class="community-footer"]
www.artstation.com##PRODUCTS-LIST
www.artstation.com##DIGITAL-PRODUCT-PREVIEW
www.artstation.com##MARKETPLACE-POPULAR-PRODUCT
www.artstation.com##SUPPORT-ARTSTATION