There is actually a question that covers this same topic, but none of the answers worked for me, at least not completely.
The accepted answer is just a link to this forum thread, and based on one of its suggestions (that didn't work for me initially), I managed to put together this:
#!/bin/bash thunderbird & while [[ $(wmctrl -l | grep "Mozilla Thunderbird") == "" ]]; do sleep 0.1; done xdotool windowactivate --sync `xdotool search --name "Mozilla Thunderbird"` sleep 0.1 # prevents flakiness xdotool key alt+F4 exit 0
Which, together with the addon
MinimizeToTray revived to cause it to minimize to tray instead of closing, works. I have it set to run automatically, and it closes the window, but the mail notification applet in the system tray still turns blue when I have an email.
The only problem is that, when logging in, you will still see the window "flash" as it opens and closes, and I find this annoying (though I'm willing to put up with it if I have to).
There is another, similar add-on called
FireTray which has the advantage that you can set Thunderbird to open automatically minimized to the system tray (and this works), negating the need for a script (all you would need to do is set up the extension, then add
thunderbird to the startup programs).
However, for reasons I don't really understand, enabling
FireTray messes up the icons for Firefox and Thunderbird. They become really blurry, and I can't figure out how to fix it. I googled to see if anyone had this problem, but I couldn't find anything.
Basically, my question is just if anyone has any ideas on either how to fix either of these problems. Either prevent
FireTray from messing up the icons, or close Thunderbird with
MinimizeToTray revived without the window flashing.
Edit: After experimenting with FireTray more, I realized that it does the same window flashing thing, which makes me think it's unlikely to prevent or hide it.