When I reached for it, I got the 'align working plane to view' which look deceptively similar.   I never use that, because I work almost exclusively in the 'legacy' screen plane mode.   But I do use the 'Look at working plane' button quite often.   Please put it back as soon as possible.   (I put quotation marks around 'legacy' because it remains the only dependable mode for freeform drawing, so please do not remove stuff that enables this mode)