Upgrade to Sphinx RTD theme v1.3.0 for Sphinx 6/7 support

[Paebbels]

Description

Finally after months of pushing and waiting, ReadTheDocs theme has been updated to v1.3.0(rc1).
See release notes: https://sphinx-rtd-theme.readthedocs.io/en/stable/changelog.html#release-1-3-0

With this update, it supports docutils v0.18 (not yet v0.19/v0.20) and Sphinx v6.x/v7.x. As this repository was forked from sphinx_rtd_theme and it's used by many repositories, an update would allow upgrading from Sphinx 5.3 to Sphinx 6.17.1 so latest documentation features and updates could be used.

Environment Info

• Python Version: v3.11
• Sphinx Version: v6.1.3v7.1.0
• RTD Theme Version: v1.2.0v1.3.0

[Paebbels]

RTD updated their theme to v1.3.0(rc1). Please update this forked theme.

[Paebbels]

Hi @umarcor.

How do we want to go on with this theme?

I have made a port to ReadTheDocs Theme v2.0.0, but I can't compile the SASS stuff. I used all your modifications in previous commits and recreated a new BuildTheDocs variant. The SASS tool chains are a mess and I ended up hand-manipulating CSS files (how the SASS preprocessor would do it). ... it's not a solution. I also figured out, that RTD theme uses way outdated SASS frameworks like bourbon (oudated), fontawesome (outdated) and neat (outdated and discontinued). Here I also learned that besides Dart, NPM, Node.js also Ruby is required + a macOS to run all that shit. The whole setup doesn't even run in Docker under WSL2.

Then I rechecked Furo, but is has some drawbacks. You asked me some time ago for my comparison - I did an updated compare on latest Furo:

• [+] It supports light and dark mode.
• [-] But it needs restyling to achieve a mixed coloring like we had with our modified BTD theme.
  So at least some (or a lot?) of handwork is needed.
• [+] Furo has better admonitions.
• [+] New Sphinx plugins support Furo and some have even better support for Furo then RTD.
• [+] My biggest criticism is the missing linking of content and navigation.
  Using a link in navigation and the navigation isn't synchronized is a very very bad user experience. It makes reading big documentations a nightmare.
• [-] Some width settings seam to be magic or unclear how Furo aligns and sizes elements.
  E.g. I'm not able to figure out how to widen the navigation bar.
  It looks like they're relying on some side effects.

Do you see any chances to get Furo to a state that it serves our needs like BuildTheDocs did?