minecraft-assets/assets/minecraft/models/block/magenta_stained_glass_pane_side.json

{
  "parent": "minecraft:block/template_glass_pane_side",
  "textures": {
    "edge": "minecraft:block/magenta_stained_glass_pane_top",
    "pane": "minecraft:block/magenta_stained_glass"
  }
}