I don’t see any place in inspect (css/ios/android) where it displays the corner smoothing value (for squircles). This is for corner smoothing NOT corner radius.
This is not something that developers can use. This feature is only made for making icons so it doesn’t make sense to put it in the inspect panel, since developers have no way to implement it in apps/websites. The only way to make it work in the product interface would be vector SVG or rasterized assets (png).
Although it was fun to learn about squircles, having this implemented into a product design tool feels like a trap. A disappointing dead end to this learning exercise. It would make more sense to move this functionality into the edit-vector-mode if this is only supposed to be used for vectors and icons.