The insert operation must return the same structures that were copied.

[NadezhdaPeskun]

Steps to Reproduce

1. Open Molecules mode (clean canvas)
2. Open KET file ketcher(11).zip
3. Select all

4. Copy (ctrl-C)
5. Paste (ctrl-V) to convas

Actual behavior

1. Copying and pasting returns different structures.

2. Save as Deilight SMILES file
3. Save as Extended SMILES file
4. Open SMILES files

Open

Expected behavior
The insert operation must return the same structures that were copied or saved to SMILES files

Environment details:
• Version 3.15.0-rc.1 Build at 2026-04-02; 15:41:30
• Indigo Toolkit Version 1.43.0-rc.1.0-gd74653443-wasm32-wasm-clang-19.0.0
• Chrome Version 144.0.7559.112 (Official Build) (64-bit)
• Win11

The Issue was found while testing #3461