For the past few weeks, a frequent complaint that has arisen is how to resize the formula bar in Power Apps.

In the past, it's always been possible to expand the height of the formula bar by dragging/resizing the bottom border, as highlighted in the image beneath.

This feature is no longer available on new apps and is now replaced with expand and collapse buttons.

The expand button resizes the formula bar to a larger, fixed height. The frequent request from app builders is how to restore the original resizing functionality.

The reason for this change is that for new apps, Microsoft has defaulted the use of the new "Power Fx formula bar". 

Whilst this new feature offers several benefits, it's not possible to expand or contract the height by dragging the bottom border. If you miss this feature and want to restore the traditional formula bar, you can do so by disabling the "Power Fx formula bar" option from the settings of the app. 

There are more details about the "Power Fx formula bar" in my post here.