github jekyll page build keeps failing

I am maintaining a github page using jekyll, and today I noticed my build keeps failing no matter what actions I take (e.g., upload files, delete files, making slight text changes in files). I am attaching the error message from “Build with Jekyll”:

Error: Logging at level: debug Configuration file: /github/workspace/./_config.yml GitHub Pages: github-pages v229 GitHub Pages: jekyll v3.9.4 Theme: jekyll-theme-primer Theme source: /usr/local/bundle/gems/jekyll-theme-primer-0.6.0 Requiring: jekyll-github-metadata Requiring: jekyll-seo-tag Requiring: jekyll-paginate Requiring: jekyll-sitemap Requiring: jekyll-gist Requiring: jekyll-feed Requiring: jekyll-redirect-from Requiring: jekyll-coffeescript Requiring: jekyll-commonmark-ghpages Requiring: jekyll-github-metadata Requiring: jekyll-relative-links Requiring: jekyll-optional-front-matter Requiring: jekyll-readme-index Requiring: jekyll-default-layout Requiring: jekyll-titles-from-headings GitHub Metadata: Initializing… Source: /github/workspace/. Destination: /github/workspace/./_site Incremental build: disabled. Enable with –incremental Generating… EntryFilter: excluded /package.json EntryFilter: excluded /CHANGELOG.md EntryFilter: excluded /LICENSE EntryFilter: excluded /Gemfile EntryFilter: excluded /README.md Reading: _posts/2013-08-14-blog-post-2.md Reading: _posts/2012-08-14-blog-post-1.md Reading: _posts/2015-08-14-blog-post-4.md Reading: _posts/2199-01-01-future-post.md Reading: _posts/2014-08-14-blog-post-3.md EntryFilter: excluded /assets/js/plugins EntryFilter: excluded /assets/js/vendor Reading: _teaching/2014-spring-teaching-1.md Reading: _teaching/2015-spring-teaching-2.md Reading: _publications/2015-10-01-paper-title-number-3.md Reading: _publications/2010-10-01-paper-title-number-2.md Reading: _publications/2009-10-01-paper-title-number-1.md Reading: _portfolio/portfolio-2.html Reading: _portfolio/portfolio-1.md Reading: _talks/2023-11-07-presentation.md Reading: _talks/2023-11-28-presentation.md Reading: _talks/2023-01-06-talk.md Reading: _talks/2022-03-31-presentation.md Reading: _talks/2024-02-02-presentation.md Reading: _talks/2024-02-09-presentation.md Reading: _talks/2023-09-27-talk.md Reading: _talks/2024-02-06-talk.md Reading: _talks/2023-11-26-presentation.md Reading: _talks/2023-10-10-presentation.md Reading: _talks/2023-12-05-presentation.md Generating: JekyllRedirectFrom::Generator finished in 0.025965185 seconds. Generating: JekyllOptionalFrontMatter::Generator finished in 0.00022088 seconds. Generating: JekyllReadmeIndex::Generator finished in 0.000534733 seconds. Generating: Jekyll::Paginate::Pagination finished in 4.859e-06 seconds. Generating: Jekyll::JekyllSitemap finished in 0.00036056 seconds. Jekyll Feed: Generating feed for posts Generating: JekyllFeed::Generator finished in 0.00065649 seconds. github-pages 229 | Error: undefined method `excerpt_separator’ for #<Jekyll::Page @name=”404.md”>

Sorry I have close to zero knowledge of CS so I can’t interpret what is going on.

Making any updates result in

pages build and deployment / build (dynamic) Failing after 24s

pages build and deployment / report-build-status (dynamic) Successful in 2s
Details

pages build and deployment / deploy (dynamic) Skipped

Looks like the build is broken due to GitHub update of Jekyll to v3.9.4, you can see more information on academicpages GitHub issue and Jekyll repo issue.

Quick-fix solution

Remove excerpt: ... config commands from top of the files:

• _pages/404.md
• _pages/about.md
• _pages/non-menu-page.md

And from your other custom files that utilise this command.

I met the same situation. It seems that this problem suddenly happened since today. I don’t know why.

I’ve been having the same issue, just started today as well after making a very minor edit to a page.

I had the same issue. Moving to Github Actions resolved the issue for me:
https://jekyllrb.com/docs/continuous-integration/github-actions/