Floating power meter will not display on keyboard press

I want to display a power meter underneath the third person character when the player presses and holds a keyboard button. Upon release the bar should then disappear.
I have created a progress bar widget and have placed it in the desired position as a widget component in the third person character blueprint.

If I set the initial visibility to Not Hit - Testable it will display in the correct position, the meter updates as it should when the button is pressed and will then disappear after the desired delay.
However; if I set the initial visibility to Hidden, it will not display when the button is pressed. How can I fix this?

As a workaround I have set the initial visibility to Not Hit - Testable but on event construct I set the visibility to hidden. Seems to work fine now.