Solution : https://service.sap.com/sap/support/notes/917904 (SAP Service marketplace login required)
Key words :
\irj\servlet_jsp\irj\root\portalapps\, portaldesigndata\themes\portal\[new_theme_name]\nav\, \server0\apps\sap, select navitation panel, design bar image, design bar, navigation panel, user creates, iview trays, firefox browser
Related Notes :
| 920332 | NW04: Central Note for Portal SP15 |
| 899888 | EP 6.0: Central Note for EP-PIN-NAV (Navigation) |