After upgrading to version 4.3.1.2 there are some missing formatcodes in Libre Office Math (for ex. %phi). I didn't finde out all of them. You can put them into the formular editor using the special character dialogue. But this is annoying. I tryed the Linux Ubuntu version and the Windows version.
Thank you for the report. This was however previously reported in Bug 80650 - lower case greek alphabet missing in localized Math symbol table w<here you can find also a workaround. I set Status to Duplicate. Jacques *** This bug has been marked as a duplicate of bug 80650 ***