[RESOLVED] Only alphabets can be used when saving a user prefab

It's not exactly a "bug", but it's very inconvenient.

I first saved the prefab, then found the file and renamed it in Japanese.
Then I opened the sandbox map in the game and checked if the name of the user prefab was displayed.
Reading and displaying worked fine, but I couldn't change the wall and overwrite it with the same name.
The game can also read the filename in the save window, but if you click on any one and try to quote it in the input form, everything except the alphabet will be replaced with an underscore.
Also, you cannot enter anything other than alphabets directly in the input form, and it will be forcibly replaced with an underscore.
So, in order to use a descriptive name, I have to give it a tentative name and then rename the file outside the game.

Why can't I enter it when most of the in-game scenes support Japanese display with proper localization?

Hi, thanks for the message - this is quite a complicated topic, so let me try to give you a more detailed explanation.

As the names you enter directly transfer to file names (same rules apply to saved games, prefabs and scenarios), the game needs to make sure these are legal, can be compressed to the zip format and also uploaded to Steam as a cloud save. More than that, as a simple check if "is this filename legal" can behave differently on different operating systems and as we need to support use cases like transferring saves between Windows and Mac, I chose a more strict check to be on the safe side.

To actually give you something helpful, let me have a look if I can for example add a tweakable to the Tweakables.xml file that you'd be able to modify on your side to disable the strict behavior, but I'd definitely consider such change too risky to be released to the whole player base.

Just to wrap up: the tweakable that disables the checks is TWEAKABLE_SKIP_STRICT_FILENAME_CHECK in TweakablesPatch38.xml.