For some reason that I can't fathom, the default email client in LibreOffice is something called sensible-ooomua. When you try to browse for a different client, you get the following error message:
There's an easy fix! In LibreOffice:
- Click on Tools in the main menu.
- Click Options... in the drop-down menu.
- In the left-hand pane, expand the Internet option.
- Select the E-mail option.
- Delete the text string sensible-ooomua from the E-mail program text box.
- Type thunderbird (or the name of your preferred client) in the text box (yep, it is that simple).
- More properly, type usr/bin/thunderbird in the text box.
- Use the browse button (to the right of the text box) and browse to usr/bin/thunderbird and then click Open.
Next time that you want to send an email from LibreOffice, this should open Thunderbird (or your chosen email client) and start a new message.
Sources & References:
- Launchpad Bug Report: Bug #841184