Downstream bug: https://bugs.launchpad.net/ubuntu/+source/xfce4-panel/+bug/747137

Hi,

(sorry, this is a bit long because this issue looks a bit tricky to me, I can't figure out why it goes wrong)

In Xubuntu natty (xfce4-panel 4.8.2), we ship the following default config for the panel (put in a dedicated dir listed first in $XDG_CONFIG_DIRS): <http://bazaar.launchpad.net/~xubuntu-dev/xubuntu-default-settings/trunk/view/head:/etc/xdg/xdg-xubuntu/xfce4/xfconf/xfce-perchannel-xml/xfce4-panel.xml>

As you can see, there are two panels: the top one is classic, with the menu, the window list, etc (plugin-1 to plugin-10, plugin-26 and plugin-27). The bottom one [let's call it panel2_0] is dock-like, so almost only contains launchers (plugin-11 to plugin-25).

When I remove the bottom panel using the preferences dialog and look at the xfconf settings, the panel count is set to 1, and all properties and plugins from the removed panel are reset.

Then, when I add back a 2nd panel [let's call it panel2_1], it "automagically" reuses the config from the 2nd panel (xfce4-panel.xml from $XDG_CONFIG_DIRS). This means that the panel style is identical (autohide, transparency), and that the plugin numerotation will reuse the free numbers, from 11 to 25. However, the panel is created empty.
Here is the tricky part:
- drag'n'dropping a first menu entry to this panel shows it correctly, and creates plugin-11, which is a launcher
- drag'n'dropping a second menu entry to this panel shows it correctly, and creates plugin-12, which is a launcher
- drag'n'dropping a third menu entry to this panel creates plugin-13, and shows the launcher from $XDG_CONFIG_DIRS, instead of showing the one that was dragged
- ... this does that weird behavior for all launchers until plugin-22, which will show the dragged menu entry...

To take the example of the xubuntu default config:
- plugin-11 was the show-desktop icon in panel2_0, using a launcher in panel2_1 works fine
- plugin-12 was a separator in panel2_0, using a launcher in panel2_1 works fine
- plugin-13 is a launcher in both cases, so whatever I drag'n'drop in panel2_0, it will always show the launcher from panel2_0 instead (exo-web-browser.desktop)
- plugin-14 is a launcher in both cases, so whatever I drag'n'drop in panel2_0, it will always show the launcher from panel2_0 instead (exo-mail-reader.desktop)
- etc. etc, until plugin-22 because it is not the same plugin type in panel2_0 and panel2_1.

I've been a bit puzzled at first, because it seemed to make no sense and show random menu entries instead of the one that was dragged, until I understood that it showed the ones from the default panel config...

Any idea why it does that?