Thunderbird issues with beta upgrade from Zorin OS 17.3 Pro to 18 Pro

Youc can do that, but I would suggest to install it maybe in Dual-Boot to see if Debian is the right Thing for You. It is in common more ... how can is say that ... more raw than Zorin or even Ubuntu.

Depending on Your Hardware and Use Case, You would have to set up a lot Stuff manually. When You take Debian Gnome for Example: It is Vanilla Gnome - not the Gnome Desktop, You know from Zorin with all the Customization and Configuration. You can set that up manually with Themes and Gnome Extensions but it needs Time and Work to get it.

Thank you, I appreciate the advice. I am seeking to experiment with setting up a pro-audio environment, for which I need Pipewire (not in Zorin 17 where I currently am), and few background tasks. I am in no immediate hurry.

And again, my manually installed .deb package was automatically removed by Zorin and replaced by their standard (Flatpak) package. So it is impossible to have the original Mozilla package installed because Zorin will delete it automatically.

Can anybody tell me how I can copy my .deb data to the default version of Thunderbird? Copying it to ~/.var/app/org.mozilla.Thunderbird/.thunderbird/ did not work.

Where did You get the .deb Version? On the Thunderbird Website they only offer a .tar File.

I decribed the command lines I entered in one of my ealier post. Don't know how to quote it, sorry.

It seems you have the .deb file from mozillateam ppa.

Isn't the profile of thunderbird somewhere at

~/snap/thunderbird/common/.thunderbird/
?
Take a look there. Do I understand you right: You want to move the profile to the snap version?

When You mark Text, You get a Window:

I guess, You mean this?

If yes, You could try something with Point 3. You can add there a lower Priority for Ubuntu and Zorin:

Package: thunderbird*
Pin: release o=Ubuntu
Pin-Priority: -1


Package: thunderbird*
Pin: release o=Zorin
Pin-Priority: -1

Add that to the File in /etc/apt/preferences.d with typing in Terminal:

sudo nano /etc/apt/preferences.d/mozilla-firefox

then copy the above and press ctrl+o to save, Enter to confirm and ctrl+x to exit.

Thanks! I will give it a try.

Yes, I thought I copy my data over to another folder and then work with the Zorin standard. But it did not work.