I have tested this with a brand new widget within a BP as it seems to be happening with all my widgets - Recently updated my project from 5.4 to 5.5 and the 'set widget visibility node is not working any more.
If I do this (as shown) the widget text does not go visible again - checking the BP debugger the visibility value for the widget is true as expected but the widget does not go visible.
If I remove the delay it goes visible from begin play but any attempts to change visbility after does not work If I put another delay before the ‘hidden’ node - it does not hide.
I can only assume this is a bug but wondering what a solution might be to fix?