Happy April 1st.
If you really want the normal textures back, here's how to get them:
- Go to your Minecraft launcher working directory. On Windows, this is
%appdata%/.minecraft
. On Mac, this is~/Library/Application Support/minecraft
. On Linux, this is~/.minecraft
. - Create the directory
versions/1.12.2-original
. - Download 1.12.2-original.json and save it to that directory. Make sure you are not saving it as a plain text file.
- Start the launcher.