Just so you know, i noticed that Steam validation (verify integrity of game files) can fail to detect corrupted files, at least in the case of Civ6 localization files. Since it's the first step people take (or should take) when they encounter bugs, it can be quite annoying. I was testing the latest (unreleased) CQUI mod and at some point had the UI disappear completely. It turned out that was caused by missing localization strings in my installation of Civ6 and not CQUI itself. However even after i validated my files i still had the issue. Finally i solved it by deleting the \Steam\SteamApps\common\Sid Meier's Civilization VI\Base\Assets\Text folder and validating again. This time Steam noticed missing files and downloaded them. If you have some persistent localization issues it could help to try this. It might also be useful to spread the word which is why i posted this as i really trusted the validation to ensure my installations were clean and it looks like there's no guarantee.