Font size options in classic editor changed to px instead of pt. How to revert?

I use the advanced editor tools in conjunction with the classic editor in WordPress. Very recently the font size option dropdown changed from sizing in “pt” format to “px” format. This is causing problems with sizing in relation to a large amount of text already sized using pt, and the need to continue with the same sizing conventions on my website, in some cases using sizes such as 10.5pt. How can I revert the editor back to my being able to select font sizes using “pt”?