Acronyms hyperlink in the index

[Angelo Graziosi]

With TL2020 I have rebuilt (macOS) some documents and noticed that using acronym package some acronyms are really hyperlink. I do not understand the logic for which some acronym are hyperlink and other not. In the attachment you can see an example of screen shot taken for a document built with TL2019 and TL2020. For what I know the acronyms should hyperlink in the text but not in their index.

On macOS  I installed TL2020 with install-tl -no-gui, i.e. I do not use MacTeX.

BTW, the acronym package seems to be updated recently, its documentation on CTAN says released on 2020.04.17! 5 days in the future...

Happy Easter,
  Angelo.