Option 1:
This means that the ssh-agent is not running. Type this in your terminal:
eval "$(ssh-agent -s)"
Then you only need retype ssh-add:
ssh-add
NB: This fix will only work for the current session. If you close your terminal, you will have to re-enter your passphrase. I recommend you couple this method with tmux, this way you can keep working with the same session. If this is not enough for you and would prefer not entering your passphrase ever again, you may also use gnome-keyring.
Option 2: Run
ssh-agent
# Output:
SSH_AUTH_SOCK=/tmp/ssh-hZQhwQlxahPX/agent.1833; export SSH_AUTH_SOCK;
SSH_AGENT_PID=1834; export SSH_AGENT_PID;
echo Agent pid 496;
# Copy and paste the first 2 lines of output
SSH_AUTH_SOCK=/tmp/ssh-hZQhwQlxahPX/agent.1833; export SSH_AUTH_SOCK;
SSH_AGENT_PID=1834; export SSH_AGENT_PID;
# Finally, run:
ssh-add
# List your keys with
ssh-add -l
Install keychain and combine it with ssh-agent to save passphrase for all shell sessions.
Df is a very handy command which reports file system disk space usage (see man df for more info). You should at least know the -h flag, which prints a human-readable result. If you ever encounter this issue, you need to type this command in your terminal:
systemctl --user stop xdg-document-portal.service
Since the latter only is a temporary fix, I encourage to also type this:
systemctl --user disable xdg-document-portal.service
If you want to know more about systemd, click on this link
Since it frequently happened after sleep mode with Arch Linux and it has been happening again with Ubuntu (strangely it never happened with Gentoo), here is the fix I have been using. You only need 2 commands:
sudo modprobe -r psmouse #kill mouse kernel module
sudo modprobe psmouse #restart mouse kernel module
Other solution:
You need to start the brave browser with this flag:
brave --disable-gpu
This means no directory is set for xbacklight. To find the directory for your xbacklight settings, run the following commands:
sudo find /sys/ -type f -iname '*brightness*'
You should obtain a similar result:
/sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight/brightness
Now, you only need to creare a symlink:
ln -s /sys/devices/pci0000:00/0000:00:02.0/drm/card0/card0-eDP-1/intel_backlight/ /sys/class/backlight
In case the above solution did not work:
sudo vim /etc/X11/xorg.conf
Section "Device"
Identifier "Card0"
Driver "intel"
Option "Backlight" "intel_backlight"
EndSection
[user]
default=username