"Visible watermark" does not work with CJK text

[hexchain]

Using CJK text as watermark results in something that looks like an encoding error:

This is G'MIC 2.9.4 and GIMP 2.10.22.

[dtschump]

Yes, unfortunately, the character set supported by the G'MIC command text is quite limited at the moment (and does absolutely not support UTF-8). Command fontchart shows the available characters. Every filter that is based on command text will have this limitation.