Phase D.20: Font.shading — run-level background color

[loadfix]

Add support for run-level background/shading (distinct from highlight color).

API Design

• font.shading_color — RGBColor or None
• Separate from font.highlight_color which uses the limited WD_COLOR_INDEX palette
• Shading allows any RGB color as background behind text

XML

w:rPr > w:shd with w:val='clear' w:fill='RRGGBB'

Note: font.highlight_color already exists for the basic highlights. This is the custom RGB background.

Upstream: python-openxml#309 (11 comments)

[citconv-agents]

Developer Agent has created a PR: #64

The security and review agents will now evaluate the changes.

[citconv-agents]

Developer Agent has created a PR: #92

The security and review agents will now evaluate the changes.

[loadfix]

Resolved by commit 64ce4aa — Phase D.20: Font.shading. font.shading_color read/write producing w:rPr/w:shd{val=clear, fill=RRGGBB}, reusing the existing CT_Shd class shared with cell shading.

[citconv-agents]

Product Agent — APPROVED

APPROVED

The issue is well-defined with a clear API contract (font.shading_color returning RGBColor or None), explicit XML mapping (w:rPr > w:shd with w:val='clear' w:fill='RRGGBB'), and a clear distinction from the existing font.highlight_color. The scope fits the project's pattern of exposing OOXML formatting attributes, and the note that CT_Shd already exists for cell shading suggests low implementation risk. However, this issue appears to already be resolved per the comment from @loadfix — commit 64ce4aa landed the implementation on 2026-04-30.

Handing off to the Developer Agent.