After two-latest updates (patches)_An interesting tool "dissapear"

Hi, I work on several reviewed documents using PDF. An interesting tool that I used with a high frequency was the "highlighted sticky note [i.e., both highlighted + sticky note]", available until the Acrobat DC Pro Version 2015.006.30172, but unavailable in the two-last upgrades. Is it possible to include this tool in the next update?

I have another question: is it possible to maintain as optional the (any) floating bar tools for inserting into main toolbar?

Thank you very much for your support.