Simulate a bad connection

Use tc to enshittify your connection:

tc qdisc replace dev ens2 root netem corrupt 10%
tc qdisc change dev ens2 root netem delay 250ms 250ms distribution normal

If this doesn't work, check that the kernel module is loaded:

modprobe sch_netem

Or, use iptables:

iptables -A INPUT -i ens2 -m statistic --mode random --probability 0.05 -j DROP