The reaction components saved in CML are partly lost

**Steps to Reproduce**
1. Launch Ketcher in **standalone** mode
2. Create reaction (e.g. cyclohexane , reaction arrow, benzene)
3. Click the Save As button. Choose  the 'CML' format.
4. Copy the CML and close the dialog.
5. Click the Clear Canvas button.
6. Click the Open button.
7. Paste the copied CML and click OK.

**Expected behavior**
Reaction is on the canvas. The opened reaction is the same as the previously created one.

**Actual behavior**
Only one structure is on the canvas. CML code has changed.

**Additional**
When reaction was saved into file (any mode) and when opened in standalone, the same issue remains.
Same issue in 2.2 standalone.