Craft strips out parenthesis in file names. Is there any way to allow () in asset file names (ex. file(1).txt)? Craft strips it out when it saves. The only way I've found is to change it via ftp and update asset indexes. 

I've set convertFilenamesToAscii => false but that didn't help.
I can't see a way... uploads ultimately get run through FileHelper::sanitizeFileName(), which has a hard-coded list of disallowed characters in a file name (including parenthesis).

https://github.com/craftcms/cms/blob/develop/src/helpers/FileHelper.php#L128-L166