If I try to change a Frame's Visibility using a Server-sided script, it doesn't work (the gui does not change visibility

..but however, using another Server-sided script, I changed the text of a Gui in StarterGui and it works????

I have no idea why it works.

What happened here was that I was able to change the text property, but not the visibility property. I'm very confused right now, I thought everything regarding changes in Gui requires a Local Script.

Other than changing the Text, I cloned TextLabels in StarterGui using a Server-sided script, and it works... why does it work???

Please help me understand why I can't change visibility but I can change a text.