https://www.reddit.com/r/XPS/comments/nnsvji/my_experience_with_dell_xps_9500_manjaro_i3_linux/
On Linux, another issue that I've had is that after waking up from suspend, I couldn't use mouse and keyboard for about 3-6 seconds, even though system was awake. Running command: sudo rmmod psmouse fixed that issue for me. Now keyboard and mouse is instantly available after wake.
For a permanent solution
echo "# Fix for 5sec unresponsive keyboard after suspend
# Source https://www.reddit.com/r/XPS/comments/nnsvji/my_experience_with_dell_xps_9500_manjaro_i3_linux/
blacklist psmouse" | sudo tee /etc/modprobe.d/blacklist-dell-fix-keyboard-unresponsive.conf