I'm using Archlinux, Gnome3 desktop, for I use fcitx, so I create a .xprofile file in Home, and add
export GTK_IM_MODULE=fcitx
export QT_IM_MODULE=fcitx
export XMODIFIERS="@im=fcitx"
when restart, I couldn't use fcitx but GTK application, the fcitx-diagnose error as link, but when I start xfce desktop, all things is OK, I don't know why Gnome3 now couldn't read .xprfile in home ?
https://bbs.archlinux.org/viewtopic.php?pid=1652981#p1652981