net-im/err depends on dev-qt/qtwebkit:4 which is ancient and will never see any security updates. If there's no upstream port available, I'd suggest to remove the USE flag.
commit 1783fcaae0c9670e4c23a01979b0d32bc945dcd7 Author: Sergey Popov <pinkbyte@gentoo.org> Date: Thu Jun 8 04:19:46 2017 +0300 net-im/err: remove support for GUI console, which relies on ancient qtwebkit Add missing USE-flag dependency for specific Python version on dev-python/xmpppy Gentoo-Bug: 620832 Package-Manager: Portage-2.3.6, Repoman-2.3.1