Comment 124 for bug 1752772

Regarding my previous comment
"4.15.0-24-generic resolved the problem for me."
That is true for my Asus N53SV laptop.

However I have a desktop motherboard with onboard
Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 11)

Where I have discovered this issue is occurring on Kernel
Linux 4.15.0-43-generic #46-Ubuntu

I have made a temporary workaround for my desktop like so:

#####
#/etc/systemd/system/fix-r8169.service

[Unit]
Description=Fix RTL-8169 Driver on resume from suspend
After=suspend.target

[Service]
User=root
Type=oneshot
ExecStartPre=[[ $(uname --kernel-release) == "4.15.0-43-generic" ]] && /sbin/modprobe -r r8169
ExecStart=[[ $(uname --kernel-release) == "4.15.0-43-generic" ]] && /sbin/modprobe r8169
TimeoutSec=0
StandardOutput=syslog

[Install]
WantedBy=suspend.target

#systemctl enable fix-r8169.service
#####

This script gives new kernels the opportunity to get it right.
If I update and the new kernel is not working, I'll update the kernel version in the systemd service.