Hello. Version: 2.9.3.9 (release folder)
MC 1.7.10; Forge 1517; Opti, FC, etc
Vanilla End stone not add GUI-chisel:

but chiseled end stone can edit:

although the texture of the end stone have been added 3 months ago:
c1389d9 04aae7f

It is planned for the future or a bug?

I also noticed that the game can not find the file:
[Client thread/ERROR]: Using missing texture, unable to load chisel:textures/blocks/endstone/EnderFrame.png, java.io.FileNotFoundException

Files EnderFrame-N-DDD.png/EnderFrame-N.png present, and without numbering no))

debug-info:
[Client thread/DEBUG] [FML/]: Unable to lookup chisel:cobblestoneWall for public static team.chisel.block.BlockCarvableWall team.chisel.init.ChiselBlocks.cobblestoneWall. This means the object wasn't registered. It's likely just mod options.
-//- chisel:obsidian2 -//- team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.obsidian2.
-//- chisel:voidstonerunic for public static team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.voidstonerunic.
-//- chisel:circuits -//- team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.circuits.
-//- chisel:arcane -//- team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.arcane.
-//- chisel:thaumium -//- team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.thaumium.
-//- chisel:tallow -//- team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.tallow.
-//- chisel:bloodRune -//- team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.bloodRune.
-//- chisel:bloodBrick -//- team.chisel.block.BlockCarvable team.chisel.init.ChiselBlocks.bloodBrick.

bug reg?

Issue already fixed a few weeks ago, is available in the 3.0 dev branch.

That's not fixed

NOT. RELEASED.