It has not got the same issues with firefox or chrome, only opera shows double results in the search.
the os is working fine as im using the os search at times as opera wont find my file in the directory, it is actually not shown during a manual search true the folder.
Version: 46.0.2597.57 (PGO) - Opera is up to date
Update stream: Stable
System: Windows 7 64-bit (WoW64)