quick fix for making compose window resizable by expanding/shrinking when textarea is resized

the textarea is resizable (though it's not convenient to do in firefox which
only shows a dragcorner in the bottomright, usually located in the bottom
corner of the screen, so there is little space left to drag the corner; the
workaround is to move the window temporarily).

webmail/webmail.ts

@@ -1375,8 +1375,6 @@ const compose = (opts: ComposeOptions) => {
 			border: '1px solid #ccc',
 			padding: '1em',
 			minWidth: '40em',
-			maxWidth: '70em',
-			width: '40%',
 			borderRadius: '.25em',
 		}),
 		dom.form(