Solution : https://service.sap.com/sap/support/notes/1590484 (SAP Service marketplace login required)
Key words :
web dynpro alv customizing maintain user specific selections, terms web dynpro abap alv export, user specific format selection, web dynpro alv, enter sap gui alv, 02import basis support package 10, 30import basis support package 5, 31import basis support package 2, sap netweaver support package, wd abap alv
Related Notes :
| 1125812 | SALV_BS_ADMIN_MAINTAIN: Activating the XXL format |
| 1080608 | Defining ABAP ALV export format for spreadsheet |