The running head skips the page the chapter opens on

[alpibrupa]

Closes #29.

Since #20 a chapter's title ran top-centre on every page of that chapter — including the chapter's own opening page, where the title is already set two inches below in 1.8em, and where book typography conventionally drops the running head.

#29 recorded this as a limitation because named page groups cannot express it, and that part was right. WeasyPrint reads :first as the first page of the document rather than of the group, so @page chapter:first suppresses only the very first chapter's opener. Alternating the names between chapters — which should have broken the grouping — does not help either. Verified on 69.0 with four chapters given alternating names:

['-', 'Title 1', 'Title 1', 'Title 2', 'Title 2', 'Title 2', 'Title 3', ...]

Openers two, three and four still print.

The mechanism that works is not page groups at all. CSS Paged Media gives string() a second argument for exactly this case — first-except yields the empty string on the page where the string was set, and the set happens on the chapter's own opening page:

['-', 'Title 1', 'Title 1', '-', 'Title 2', 'Title 2', '-', 'Title 3', 'Title 3', '-', 'Title 4', 'Title 4']

One keyword. No named pages, no alternating classes, continuation pages untouched.

Verified across all four books in the series — 67 chapter and appendix openers, none carrying a running head; 328 continuation pages that still do:

book	pages	openers	openers with a head	pages with a head
production	163	17	0	137
evidence	96	17	0	70
ledger	96	17	0	70
decision	76	16	0	51

144 tests pass, ruff clean, 4 import contracts kept. The new test pins the keyword itself, since the behaviour rests entirely on it and a well-meaning simplification back to string(chaptertitle) would silently restore the bug.

🤖 Generated with Claude Code