One of the most annoying changes with Gmail has to be the compose mail pop-up box, which floats at the corner of your screen. Google has included a full screen toggle button on the top of the compose box. I personally like to compose mail on a full screen rather than rolling my eyes over to the left corner of my screen every time to see whether I’m typing correctly. I also found it a bit annoying to click the full-screen toggle button every time I compose a e-mail.

Fortunately, It’s very easy to make the full screen compose as a default setting

How it works:

Compose a new mail and the usual compose box would pop-up

Click on the little arrow you will find in the lower left corner of the compose box. Then choose Default to full-screen

Bingo! Now every time you compose a mail you will get a full-screen compose box. If you want the newer compose box, then simply repeat the steps again.

Source: www.devilsworkshop.com

Thank to R.Saravanan, Sys Admin