LaurentGomila/SFML — comment on commit b65b19343abf9e1becd13b3fcd87b003f67eb2a3
File:  line 0
By LaurentGomila:

Textures were stretched by a huge factor, and it didn't happen if you used a vertex shader. So obviously the texture matrix applied to integer texture coordinates were badly handled by the driver in the FFP.

But it probably didn't happen with all graphics cards / drivers. I remember someone who could get rid of the bug by switching to the free driver on Linux.