Vietnamese Wikipedia for instance; most of its diacritics really look weird and, it is what you get when you insist on using a script that does not really consider a tonal language.
The Devanagari script is used for many languages and the assumption that all these languages use exactly the same characters is wrong. Kashmiri uses characters not used for for instance Hindi.
The result is that a font that does not include the additional
characters does not suffice, the keyboard method will not be the same.
We often do not have enough knowledge to support the languages that have a Wikipedia. There are also languages waiting in the Incubator
needing proper support. We want to support all languages well and, we
want to support a language well from the start. Join the "language support team" for your language and help us ensure that we can support your language properly.