[MinimizeToTray] a few more things

[Dino]

Hi again!

I just noticed there's a problem with the icon in the tray.

When I minimize Thunderbird to tray, and then right click on the tray 
icon, the standard windows taskbar menu pops up.

And if you are writing a message at that time like I am right now, you 
wont be in able to type anything, but you will be in able to select the 
text. The opened pop up will still be active during that time, until you 
select something from it, or click on  a windows taskbar.

So these things I think are very important.

Here's a suggestion: you could add a option to make thunderbird load 
minimized only when windows starts. For those of us who like to have it 
always on, it could be very useful, instead of having to bring it up 
every time we start it manually.

Please keep me informed!

Dino