The idea of Plain Text requires the operating system to provide a font to display Unicode codes. This font is different from OS to OS for Singhala and it makes orthographically incorrect glyphs for some letters (syllables) across all operating systems. For instance, the 'reph', the short form for 'r' is a diacritic that normally goes on top of a plain letter. However, it is wrong to go on top of some letters like 'ya' or 'la' in specific contexts. For Sanskritic words or names inherited by modern languages, such as कार्य, IAST: "kārya", or आर्या, IAST: "āryā", it is apt to put it on top of these letters. By contrast, for similar sounds in modern languages which result from their specific rules, it is not put on top, such as the word करणाऱ्या, IAST: "karaṇāryā", a stem form of the common word करणारा/री, IAST: "karaṇārā/rī", in the Marathi language. But it happens in most operating systems. This appears to be a fault of internal programming of the fonts. In Mac OS and iOS, the muurdhaja l (dark l) and 'u' combination and its long form both yield wrong shapes.