Combining diacritics appear on following character

**Context:** I haven’t tested this extensively, but I encounter it in text representing ancient languages where a macron is use to show vowel length and an acute is used to show accent or stress. I use a combined vowel with macron followed by a combining acute. This renders correctly in Source Sans Pro and Source Serif, but I’m often editing in HTML and editors like to force monospaced fonts.

While this isn’t a huge problem (since the ultimate display will be some other font), it can make the text hard to read, especially if the following character also has (a) diacritic(s).