[...] Conclusion


If you use and like Stylish, please uninstall it and switch to an alternative like Stylus, an offshoot from the good old version of Stylish that works in much the same way, minus the spyware.

This script installs the latest GitHub versions of some fine GNOME themes into the current user's .themes folder. Run the script again whenever you want to get the latest theme updates. Many of these themes are updated frequently with bugfixes and enhancements.

It supports GNOME versions 3.22 and above.

################################
#ajout perso sécurité du réseau#
################################
# IP Spoofing protection
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.default.rp_filter = 1

# Ignore ICMP broadcast requests
net.ipv4.icmp_echo_ignore_broadcasts = 1

# Disable source packet routing
net.ipv4.conf.all.accept_source_route = 0
net.ipv6.conf.all.accept_source_route = 0
net.ipv4.conf.default.accept_source_route = 0
net.ipv6.conf.default.accept_source_route = 0

# Ignore send redirects
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0

# Block SYN attacks
net.ipv4.tcp_syncookies = 1
net.ipv4.tcp_max_syn_backlog = 2048
net.ipv4.tcp_synack_retries = 2
net.ipv4.tcp_syn_retries = 5

# Log Martians
net.ipv4.conf.all.log_martians = 1
net.ipv4.icmp_ignore_bogus_error_responses = 1

# Ignore ICMP redirects
net.ipv4.conf.all.accept_redirects = 0
net.ipv6.conf.all.accept_redirects = 0
net.ipv4.conf.default.accept_redirects = 0
net.ipv6.conf.default.accept_redirects = 0

# Ignore Directed pings
net.ipv4.icmp_echo_ignore_all = 1

###########################
#ajout perso divers tweaks#
###########################

vm.swappiness = 2
vm.laptop_mode = 5
vm.dirty_writeback_centisecs = 3000
vm.dirty_expire_centisecs = 3000
vm.vfs_cache_pressure = 50

#Other network tweaks
net.core.somaxconn = 1000
net.core.netdev_max_backlog = 5000
net.core.rmem_max = 16777216
net.core.wmem_max = 16777216
net.ipv4.tcp_wmem = 4096 12582912 16777216
net.ipv4.tcp_rmem = 4096 12582912 16777216
net.ipv4.tcp_max_syn_backlog = 8096
net.ipv4.tcp_slow_start_after_idle = 0
net.ipv4.tcp_tw_reuse = 1
net.ipv4.ip_local_port_range = 10240 65535

#########################
recharger fichier avec :       sysctl -p
#########################

Icon themes in screenshot are:
Boston icon theme https://www.gnome-look.org/p/1012402/
Ozon icon theme https://github.com/ozonos/ozon-icon-theme/tree/master/Icons

thème Thunderbird