• ctp_1.2_MCv3
  -CTM-MC1.12-0.2.3.9

Optifine is NOT installed.

The problem is still relevant.

Oh closed it because because it was previously reported on the ctm mod tracker

Is it safe to assume this won't be fixed or doesn't have a fix action being worked on?

They will be fixed next update 1dd8996

Thank you for the update!

Erm, any chance an update could be pushed? I don't want to be "that guy"

If you're still looking for a simple solution @Alaberti, you can just copy the pane_side.json and pane_side_alt.json from the minecraft/models/block folder into your ressource pack and proceed the following modifications :

• In pane_side.json : "west": { "uv": [ 16, 0, 9, 16 ], "texture": "#pane" },
  become "west": { "uv": [ 0, 0, 7, 16 ], "texture": "#pane" },
• In pane_side_alt.json : "west": { "uv": [ 7, 0, 0, 16 ], "texture": "#pane" },
  become "west": { "uv": [ 9, 0, 16, 16 ], "texture": "#pane" },

The only remaining problems are the edges inside a tall window (pack improvement feature) and the disconnected textures between panes which make corners and those who are straight (bug in the mod : issue reported here)