How can I replace Geary when trying to send files directly via mail with Thunderbird? I already set Thunderbird as the mail application in the system settings, but I still have to open a new mail account when using the right-click-functionality (which I don't want).
You can add this functionality by installing the
thunderbird-contracts package. Unfortunately it's only available in the elementary OS daily PPA.
It's not recommended to add the daily PPA to your sources, since it contains unstable versions of several system components and may break your system!
Download the desired package and install it manually:
Uninstall Geary to remove the other "Send by e-mail" entry in your context menu.
The "Send by email" function in Files only works with Geary. Thunderbird doesn't provide this integration feature.
Had same problem, I solve this issue doing :
Download files thunderbird-attach and thunderbird-attach.contract from here
Move file :
mv thunderbird-attach /usr/bin/
mv thunderbird-attach.contract /usr/share/contractor/
Make thunderbird-attach executable :
chmod +x /usr/bin/thunderbird-attach
Adapt last line thunderbird-attach.contract to :
Delete Geary Contract file.
I am not sure, but it might help if you uninstall Geary completely, or purge it. Of course you cannot use Geary any longer, but if you want to use Thunderbird as your default mail app, it's not of any use!
By uninstalling Geary elementary OS is forced to use Thunderbird as its default (ONLY!) mail app.