Description
I think in the past or even current, Adobe Acrobat Reader, and also the (x)dvipdfmx/XeTeX people treat(ed) the Adobe-Identity cidmap as a direct cid/gid to Unicode mapping, for the purpose of text extraction and what not.
Well, the Adobe Source CJK fonts, and Google Noto CJK fonts definitely not - in their usage, it is just "because I said so" custom encoding and carries no meaning whatsoever in relation to Unicode.
Unfortunately fontforge takes the former interpretation, and this causes the corruption of the encoding vector during Re-encode ( #3080 ). Simply deleting the file and forces fontforge not to treat Adobe Identity as direct cid->Unicode mapping, forces fontforge to treat the cmap properly and fixes the problem seen in #3080 .
So I suggest either simply deleting the cidmap, or at least provide an scripting API to selectively disable its use. Otherwise you'll not be able to process Adobe Source CJK / Google Noto CJK properly.