Solution : https://service.sap.com/sap/support/notes/444054 (SAP Service marketplace login required)
Key words : 
tools -> customizing objects -> cross-system viewer, customizing cross system viewer, customizing cross-system viewer, additional 50-digit text fields, basis release sap web, sap standard system, copy individual entries, edit -> interactive transfer, sm30 maintenance dialog, address_into_printform function module
Related Notes : 
       
| 807508 | Input help for "Country" field in PC-UI displays no text | 
| 795147 | Country names in T005T-LANDX50 | 
| 755203 | Country name in address print too short | 
| 603152 | Country Codes for Serbia and Montenegro |