Sending documents as attachment: Libreoffice with Thunderbird 78.3.2 - Ubuntu 20.04

I cannot integrate Thunderbird 78.3.2 as a mail client for sending documents directly from LibreOffice.

What do I do: - in Writer → Options → Internet → E-Mail - E-Mail program: thunderbird

Is this because I installed Thunderbird with Snap?

  • OS: KDE Neon 5.20 (based on Ubuntu 20.04)
  • Mail client: Thunderbird 78.3.2 - installation with snap (because from the standard repositories only the outdated 68 versions can be installed)
  • LibreOffice via PPA

Thanks for your help!

Is this because I installed Thunderbird with Snap?

Could be.

Can you choose (BROWSE) to the actual SNAP executable, as opposed to just typing in ?

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