change uncommon currency symbols in japanese.txt to 3 letter codes to avoid fonts be rejected for missing characters

[BPplays]

some fonts dont have symbols for less common currency symbols so it might be worth considering changing them to 3 letter codes in japanese.txt and others if there are any. for example ESP (₧), FRF (₣), GRD (₯), NLG (ƒ), RUR (₽), TRY (₺), KRW (₩), RUB (₽), INR (₹)

[Eddi]

Do you have any examples of fonts that do and don't have these symbols?

[peter1138]

This is now implemented in https://github.com/OpenTTD/OpenTTD/pull/11061, with screenshot examples of the problem.

Most of the currency symbols are not actually used in the currencies in game for this very reason. This only affects the translations of the currency names, which being up to translators, did not restrict these symbols.