[Bug] OpenType features adds extra space at the end of Japanese text

[RichardShigeta]

Hi team,

I believe I’ve found a bug regarding text rendering in Dorico.

When using OpenType features to enable proportional width (such as palt/Proportional Alternate Widths) in Font Styles, Dorico incorrectly adds an extra, unwanted space at the very end of the Japanese text string.

The text is rendered correctly, but an unexpected extra blank space is appended to the end of the string.

(macOS 26.3.1 / Dorico Pro 6.2.30)

[Andro]

Is it something to do with double width Unicode Japanese glyphs? Have you tried alternative Japanese fonts?

Des it have something to do with the fact that Japanese uses a full width space to separate new paragraphs?

[Richard_Lanyon]

Could you attach a small example project that demonstrates the issue?

[RichardShigeta]

Thank you for your reply. I have attached the project file, though it might not be fully meaningful on its own, so please use the following steps to reproduce the issue from scratch:

• Open the Edit Font Styles dialogue and set the font for Horizontal Line Font to a Japanese font (e.g., ‘Noto Sans JP’). Leave the OpenType Features blank for now.

• Add a horizontal line to the score and input some Japanese text (Hiragana or Katakana) in the line text. If you don’t have a Japanese input environment, please copy ううううう.
  

  

  At this point, the text is rendered correctly with proper alignment:
  

  

• Reopen the Edit Font Styles dialogue and enable ‘Proportional Alternate Widths’ (palt) in the OpenType features for Horizontal Line Font.

• The characters will now become proportional and narrower, but the overall bounding box/width of the text string remains unchanged, causing the text to look shifted to the left (leaving an extra space at the end):
  

  

OpenType_issue_test.dorico (1.5 MB)

[Richard_Lanyon]

Thanks very much for the clear reproduction steps. We’ll take a look.