Thanks @mhartington finally. min-height is the solution. But when toolbar height increase every inner item stucks middle of the container. Must be change display value with block or something else.
I am trying to do the opposite thing in Ionic4: get a toolbar about half its normal size. This is how it looks normally with the toolbar at its normal size:
Toolbar height is affected alright, but the content is not adjusting automatically. Any ideas of how to get the inner elements realign to the new height?