Content matching patterns with Japanese text

I recently had some difficulty creating a pattern to match a Japanese-formatted date in a file. Here's the desired format (YYYY年MM月DD日):

Unfortunately, all the Japanese characters disappear when I try to edit the pattern:

Is there any way to edit Japanese characters in content matching patterns?

Unfortunately, all the Japanese characters disappear when I try to edit the pattern:

Is there any way to edit Japanese characters in content matching patterns?