When KTimeTracker is started early during Gnome 3 loading, the icon of KTimetracker does not appear in the icon tray. I use "Topicons plus" Gnome extension. Workaround: pkill ktimetracker ktimetracker & KTimetracker 4.14.10
Note that ktimetracker was removed from kdepim on May 2, 2014, which is more than three years ago: https://cgit.kde.org/kdepim.git/commit/?id=cd0ee7e149270ce17d5fdab95b19adc960b80ad8 So I don't think this bug will be fixed.
Hello! Sorry to be the bearer of bad news, but this project has been unmaintained for many years so I will be closing this bug.