Add start minimized and minimize to system tray in thunderbird

[Jonylentz]

Please add these options as a native feature of thunderbird. There are multiple posts around the internet searching for it and even add-ons made to workaround this issue.
Not having these options greatly reduce the user-friendly aspect of the software, it is an e-mail client and is supposed to be opened at all times to check and receive new e-mails... I shouldn't have to search for an third-party add-on just to make this work even if the add-on code is reviewed by mozilla, I am trusting my e-mail access to it and this is key to multiple sensitive and personal info.
Please make this a feature

[MarebulFL]

I'm joining the thread hoping this will be added soon within ESR.

Minimize button : untouched behavior, minimizes to the taskbar where I store my currently using applications

Close button : altered behavior, stores Thunderbird in the systray, where I store my idle (not currently using) applications.

Currently available option only alters the minimize button which then minimizes in tray instead of taskbar (the Alt+TABable ones).