Opera 5, released on December 6, 2000, was the first version which was ad-sponsored instead of having a trial period.[18] Version 5 also supported ICQ, but this was dropped from later versions.
Opera supported OS/2 for the first time, requiring WarpIN and Odin to be installed.[19]
Opera 5.10 (April 2001) was the first version to recognize mouse gestures,[20] but this feature was disabled by default.