Bug Report: Syriac Characters Not Connecting Correctly in Word for Mac

Dear Microsoft Support Team,

I would like to report a text rendering issue with Syriac (Aramaic) script in Microsoft Word for Mac.

The problem:

When writing Syriac text in Word for Mac, the letters connect correctly until I add certain vowel marks or diacritical dots. As soon as these marks are inserted, some letters become disconnected.

For example:

Without diacritics: ܚܝܐ

The letters connect correctly.

With diacritics: ܚܝ̈ܐ

The connection between the last two letters breaks, even though they should remain connected (see Screenshot 1 below).

The issue occurs with different Syriac fonts, including Serto Jerusalem.

Unicode Details

The affected word consists of the following Unicode characters:

U+071A – SYRIAC LETTER HETH

U+071D – SYRIAC LETTER YUDH

U+0308 – COMBINING DIAERESIS

U+0710 – SYRIAC LETTER ALAPH

The issue occurs specifically when the combining character U+0308 is inserted between U+071D and U+0710.

U+0308 is a Unicode combining mark representing two horizontal dots above the preceding letter.

It should not interrupt the connection between the Syriac letters.

However, Word for Mac appears to treat this combining mark in a way that breaks the connection between the letters.

What I have tested:

I tested the exact same text using the same font in several applications:

• Microsoft Word for Windows – Works correctly
• Microsoft Word Online – Works correctly (but wrong when convert it to pdf)
• LibreOffice on Mac – Works correctly
• TextEdit on Mac – Works correctly
• Microsoft Word for Mac – Does not work correctly

Troubleshooting Already Performed

I have already tried the following:

Tested several Syriac fonts, including Serto Jerusalem.

Enabled all OpenType ligatures.

Enabled contextual alternatives.

Tested right-to-left text formatting.

Tested different complex-script settings.

Tested inserting Unicode Zero Width Joiners (U+200D).

None of these changes resolved the issue.

I also tested the text using HarfBuzz 14.6.0, which correctly selected the initial, medial and final Syriac glyph forms, even when U+0308 was present.

Software information:

• Microsoft Word for Mac
• Version 16.113.4 (26100421)
• Font: Serto Jerusalem (also tested with other Syriac fonts)

Screenshots attached:

1. Screenshot 1 – Word for Mac: Shows the incorrect rendering, where the Syriac letters become disconnected.

Screenshot 2 – LibreOffice on Mac: Shows how the same text appears correctly with connected letters.

Expected Behavior

Syriac letters should remain correctly connected when vowel marks or combining diacritics are inserted, as they do in Word for Windows, Word Online and LibreOffice (see Screenshot 2).

Request

Could you please investigate this issue and determine whether there is a bug in Word for Mac's handling of Syriac Unicode text shaping?

I would appreciate any information about an available workaround or a possible fix in a future update.

Thank you for your assistance.

Best regards