Thanks, I will add it to the list.

Another interesting fact: About 50% of the DN users have an ad blocker.

So are the photos on TheStocks.im.

No! The photos from Super Famous, Startup Stock Photos, Magdeleine and Getrefe are not under the CC0 license. If you use the photos from these sources you have to give credit, provide a link to the license, and indicate if changes were made.

Thanks. I am currently working on a better search function :)

Yes

But you have to check dozen of sites to find the photo you are looking for and you have to check the license of each photo. Pexels solves these problems.

Pexels also collects the best free photos from many sources. The advantage of Pexels is that all photos are under the Creative Commons Zero license (free for commercial use, no attribution required) and that you can search for photos. With Pexels it's easier to find a great photo without worrying about license issues.