Documentation

#132220 has broken EPUB builds of documentation. This has been only partially fixed in #133720, because yet configuration of sphinxext-opengraph adds not closed tags to every page.

sphinx-doc/sphinxext-opengraph#136 and sphinx-doc/sphinxext-opengraph#137 have been opened upstream, but the PR is not merged.

Status update [2025-07-14]: now (after skipping OpenGraph custom tags in Docs conf.py) only 8 chapters fail to render in EPUB format. It can be addressed by any of sphinx-doc/sphinxext-opengraph#120 and sphinx-doc/sphinxext-opengraph#137, as far as I'm concerned. Adding a CI check definitely should help with the stability of EPUB build. Last year Inada made an effort to fix the EPUB (#118689).

Linked PRs

• gh-136155: Docs: only add custom OpenGraph protocol meta tags for HTML builds #136187
• gh-136155: Docs: check for EPUB fatal errors in CI #134074
• [3.14] gh-136155: Docs: only add custom OpenGraph protocol meta tags for HTML builds (GH-136187) #136382
• [3.13] gh-136155: Docs: only add custom OpenGraph protocol meta tags for HTML builds (GH-136187) #136383
• [3.12] gh-136155: Docs: only add custom OpenGraph protocol meta tags for HTML builds (GH-136187) #136406