Resetting Xfce Panels to default settings?

XFCE stores it's configuration for the running session in xfconfd. Feel free to back up the files you're going to delete first.

1. Shut down the panel first, xfce4-panel --quit
2. Kill the xfce4 configuration daemon, pkill xfconfd
3. First delete settings for the panel, rm -rf ~/.config/xfce4/panel
4. Clear out the settings for xfconfd, rm -rf ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-panel.xml
5. Restart the panel, run xfce4-panel. This will respawn xfconfd automatically. Note if you need or want to restart xfconfd manually know that on my installation it was in /usr/lib/x86_64-linux-gnu/xfce4/xfconf/xfconfd which was outside of $PATH.

This clears it for the running session, regenerates the files, and sets up the default for future sessions.

Want it in one line?

xfce4-panel --quit ; pkill xfconfd ; rm -rf ~/.config/xfce4/panel ~/.config/xfce4/xfconf/xfce-perchannel-xml/xfce4-panel.xml ; xfce4-panel;

The only thing I can say that would make it easier to just run:

rm -r ~/.config/xfce4

Then simply log out and back in. This will just reset xfce4 back to default. I'd recommend avoiding the -f flag unless necessary especially if you are using the sudo command which is not an issue here but anyway. Using only the minimal force necessary is always a good idea.

This also limits the commands a user has to enter, you can also open up your file manager and select view hidden files and go into the .config folder and right click and delete the xfce4 folder and then log out and back in. No commands necessary.

In my case I didn't want to switch the entire panel to the default, I just wanted to switch to the default layout because I recently upgraded from Xubuntu 16.04 to 18.04 and there were some changes to the panel plugins.

Here's what I did:

1. Right-click anywhere on the panel (except for one of the open window buttons) > Panel > Panel Preferences
2. Click Backup and restore
3. (Optional) Click the Save Configuration button to save your current configuration
4. In the list of configurations, select the one corresponding to your version of Xubuntu. For example, I'm using Xubuntu 18.04, so I selected Xubuntu Bionic.
5. Click Apply Configuration