Created attachment 204453 [details] R.docx Attached DOCX contains R symbol for Set of real numbers. On the bottom is image how it looks in MSO. When opening in LO, simple R is shown, which is not correct. When saved and reopened, also in MSO simple R is shown. LO has that symbol in Formula-Elements-Set Operations. So this look like filepen bug for DOCX. OO did not read it. This seems implementation error somewhere in 3.x.
Within document.xml you can find this : <w:rPr><w:rFonts w:ascii="Cambria Math" w:hAnsi="Cambria Math" w:cs="Arial"/> <w:color w:val="000000" w:themeColor="text1"/><w:sz w:val="48"/><w:szCs w:val="48"/></w:rPr> <m:t xml:space="preserve"> R </m:t></m:r> So, this is really an L letter within a specific (non-free) font. Could you try it on a reversed way ? That is, compose first your document within LO, using the setR symbol in LO Math, save your document in docx format and open it in MS Word. What do you get ?
Created attachment 204454 [details] Variant
I did the aforementioned experiment. It seems that in the resulting docx file Lo uses the Unicode U+211D character.