Post: enable addons by default

Follows the plan we described in:
readthedocs/addons#72 (comment)

content/posts/addons-by-default.md

@@ -0,0 +1,100 @@
+title: Read the Docs Addons enabled by default
+date: 2024-07-15
+description: Read the Docs Addons will be enabled by default to all projects soon
+category: Changelog
+tags: builders, sphinx, addons
+authors: Manuel Kaufmann
+status: published
+image: /images/addons-by-default.jpg
+image_credit: Photo by <a href="https://unsplash.com/@silvawebdesigns?utm_content=creditCopyText&utm_medium=referral&utm_source=unsplash">Nathan da Silva</a> on <a href="https://unsplash.com/photos/macbook-pro-beside-white-ceramic-mug-on-brown-wooden-table-k-rKfqSm4L4?utm_content=creditCopyText&utm_medium=referral&utm_source=unsplash">Unsplash</a>
+
+We are announcing the introduction of [Read the Docs Addons](https://about.readthedocs.com/blog/2024/04/enable-beta-addons/) to all the projects by default starting on **October 7, 2024**.
+Read the Docs Addons is the new modular implementation of all the features Read the Docs adds on top of your documentation:
+analytics, flyout menu, notifications and search, among others.
+
+Since Read the Docs started, every time it ran a build,
+a set of extra configuration were automatically added to make the integration easier.
+This manipulation happened at Sphinx's `conf.py` and MkDocs's `mkdocs.yml` configuration files,
+and included the following:
+
+- Adding JS and CSS files.
+- Defining the Read the Docs theme by default.
+- Injecting extra data into Sphinx's `html_context` to make it available from Jinja2 templates.
+- Configurating the LaTeX engine for Japanese and Chinese projects.
+- Setting the canonical URL based on the domain defined in Read the Docs.
+- ... and others.
+
+This manipulation has worked great for **+10 years** for most of our projects.
+However, for some users this "behind the scenes" manipulation was hard to understand
+and mislead what was going on when building on Read the Docs,
+since results may differ from when building locally.
+
+The introduction of Read the Docs Addons [last year](https://blog.readthedocs.com/addons-flyout-menu-beta/),
+has proved that all these features can be added on top of the documentation without having to manipulate project's configuration at build time,
+removing these differences between building locally and on Read the Docs;
+making users to always get the result they were expecting.
+
+We've been enabling Read the Docs Addons by default to all projects using `build.commands` since then
+--which was a workaround for those users wanting to skip this "behind the scenes" config manipulation,
+and it also showed great success.
+
+Another step towards this direction was the removal of [YAML manipulation](https://about.readthedocs.com/blog/2024/03/mkdocs-yaml-manipulation/) for all MkDocs projects, on Aril 2024.
+Since then, all projects building with MkDocs are already using Read the Docs Addons and they haven't reported any big issues.
+
+All of this step-by-step changes have given us the confidence to make the last step and **plan the removal of the config manipulation for Sphinx projects** as well,
+which is the most used documentation tool on Read the Docs,
+and that's why we left it for the end.
+
+
+## Deprecation timeline
+
+We understand this change is going to affect _all the projects_ building on Read the Docs,
+so we have a timeline to make this deprecation easier for our users.
+Keep these dates in mind and prepare your projects for the changes:
+
+- **July 29, 2024**: enable Read the Docs Addons for _all **new** projects_ created.
+- **October 7, 2024**: enable Read the Docs Addons for _**all projects**_.
+
+
+## How does it affect my projects?
+
+It's worth to note there are two big different types of changes that will affect your projects:
+at build time, and visually.
+Depending on the configuration of your project, it could be affected by one, both or none of them.
+
+### At build time changes
+
+As we mentioned before, all the Sphinx's `conf.py` file manipulation won't happen anymore at build time.
+This means that if your project were using any of these extra configuration,
+those won't be available at build time anymore and some features may not work as expected,
+or the build could fail completely.
+
+In case you've found any difference in behavior after Read the Docs Addons has been enabled
+(see [How to opt-in to addons _now_](#how-to-opt-in-to-addons-now) to enable addons manually),
+you can try installing the [`sphinx-build-compatibility`](https://github.com/readthedocs/sphinx-build-compatibility/) extension we've created
+to allow keeping the "behind the scenes" manipulation behavior at build time while you can dig more on these changes and perform the migration gradually.
+
+### Visual changes
+
+Even if the build has completed successfully, there may be some visual changes you noticed.
+Version and pull request notifications were completely re-designed and the flyout menu has been moved to a floating position in the bottom right,
+for example.
+
+Depending on your project's configuration, the documentation tool and the theme you are using, you will notice these differences.
+We plan to release a new version of our theme to keep the flyout menu at the bottom left integrated with the navbar soon,
+and we are talking to other theme authors to communicate these changes and work with them towards a better integration.
+Expect news around this visual changes in the following months.
+
+
+## How to opt-in to addons _now_
+
+Read the Docs Addons is already available for all users that want to start using it on their projects.
+In case they want to prepare themselves for the migration, or make usage of the new features from Read the Docs Addons, like the [DocDiff](https://docs.readthedocs.io/page/pull-requests.html) for example.
+If you want to enable Read the Docs Addons in your project, [follow these steps from our documentation](https://docs.readthedocs.io/page/addons.html#enabling-read-the-docs-addons).
+
+
+## Feedback
+
+[Let us know](https://docs.readthedocs.io/page/support.html) any feedback you may have about this change or any of the addons.
+We are happy to work together to keep improving them or fix any issue you may have with the migration.
+