"From" address should show a tooltip with the complete email address

Running pantheon-mail 1.0.5 on elementary OS 0.4 Loki.

I have a 720p display resolution and I prefer to keep my mail client unmaximized. When the size of the window is less, the "From: " address is often not entirely visible.

To counter this, I have tried to hold my cursor on the address field, thinking a tooltip with the full email address might show up, but it doesn't.

The only way to see the full email address is to expand the width of the window and then contract it back to your preference.