Greek letter with accent being capitalized

I would like to report a strange behavior occurring to me in both Figma and SwiftUI / UIKit text rendering.

The greek accented letter "ή" is rendered as the uppercase counterpart:

Example @ Figma:

Example with a SwiftUI text:

Start by reproducing the rendering of the Greek letter "ή" in Figma and in SwiftUI/UIKit, using the examples in the issue. Compare the displayed lowercase and uppercase forms, then verify that the accented lowercase letter renders correctly in each environment.

Written by the indexing model from the issue text.