I know Stone slabs for the most part have always had a horizontal line in the middle and in some snapshots, their texture glitches and you get a 'solid' or 'clean' version of the double slab block. I suggest that we have both! The 'solid' version should be obtainable by shift-clicking the second slab. If you aren't shift-clicking, you'll get the regular version.
In the Image you can see the normal version of double stone slab blocks on the left, and the glitched version from a snapshot on the right.
Being a nerd is nothing to be ashamed of. Nerds rule the world! Who invented the internet? Nerds. Who created personal computers and smart phones? Nerds. Who made every video game you've ever played and ever will? Still nerds. Who sent probes to distant planets? Nerds, nerds and more nerds! I'm a nerd and I'm proud.
Sounds Good! I don't know if you were playing in a recent snap shot, though there was a bug where stone slabs placed down together would make Double Stone Slabs, it was a neat change. And since that bug has been fixed I've found myself using /fill ~ ~ ~ ~ ~ ~ double_stone_slab 8 a lot more than any time before!
" glitched version from a snapshot " That's how I got these textures in my photo. I believe 2 or 3 weeks ago was when the glitch happened again.