Admin > General Settings > General tab > "Display notes in the bank account list if any of the bank accounts have notes available".  

When the config setting  "Display notes in the bank account list if any of the bank accounts have notes available" is ticked, the bank notes will be displayed in the bank account list in the banking tab on the Partnership/Company Details window.  The bank notes column will only be displayed if there are Bank Notes entered for at least one of the bank accounts in the list.

Notes are not displayed in the Main Client Bank Account List. The notes for Client Bank Accounts can be seen in the Partnerships or Trading Companies > Banking tab > Bank list

The Notes column is displayed when the config setting is ticked and there are Bank notes to display.

How to add notes in the Bank Account Details