"A file was included is a symlink or does not exist" when trying to overwrite _includes/archive-single.html using Github pages

[Rainymood]

Environment

• Minimal Mistakes version: I don't know, I run it as a remote theme
• Ruby gem or remote theme version: locally 2.6.3, remote 2.7.1
• Jekyll version: 3.9.0
• Git repository URL: https://github.com/Rainymood/rainymood.github.io
• GitHub Pages hosted (if yes provide URL to site): https://www.janmeppe.com/
• Operating system: Mac OSX

Expected behavior

I copy over _includes/archive-single.html from the original minimal mistakes repository to _includes/archive-single.html and tweak it a bit to add the date in the title.

I can run and build it locally and the change works. Then I push it to github pages, view the commit here

Actual behavior

Page doesn't build anymore and I get this build error:

A file was included in /_layouts/single.html that is a symlink or does not exist in your _includes directory.

I found this github issue but I don't really understand what it means:

It looks like you're using a custom source. You're not allowed to use custom sources in your Jekyll sites on GitHub Pages. They override it to your repo's top directory. So it's looking for ./_includes/... rather than ./docs/_includes.

Does this mean I can not overwrite any of the layouts? I want to tweak my minimal mistakes theme a bit, is this possible when using github pages or is this off limit?

[mmistakes]

Overriding _includes works fine. The issue is this line in your _includes/archive-single.html

<!-- <a href="{{ post.url | relative_url }}" rel="permalink">{{ title }} {% include date.html %}</a> -->

Doesn't matter to Jekyll that you've commented it out in the HTML, you're trying to pull in _includes/date.html which doesn't exist in the theme nor in your local _includes folder.

Either rename it to page__date.html to use what's bundled in the theme, or create _includes/date.html in your repo.

[Rainymood]

That makes a lot of sense. _includes/date.html is still uncommitted indeed.

Thanks for clearing this up.