Flyout: keep the anchor when changing the language

[rdswift]

Similar to #131, currently anchor in the URL is always removed while changing the language through the side bar menu.

[humitos]

Thanks for reporting this.

Here is an example where this is happening:

1. Go to https://docs.godotengine.org/en/stable/about/faq.html#which-programming-languages-are-supported-in-godot
2. Switch the language to Spanish
3. You are redirected to https://docs.godotengine.org/es/4.x/about/faq.html (note there is no # anchor anymore)

It should go to https://docs.godotengine.org/es/4.x/about/faq.html#which-programming-languages-are-supported-in-godot

[rdswift]

Yes, that's a problem, but not the one I was reporting. I meant that the entire html file name was being removed from the URL when changing the language (or version) from the side bar (not the flyout). Using your example website:

1. Go to https://docs.godotengine.org/en/stable/about/list_of_features.html
2. From the pulldown at the bottom of the left sidebar (not the flyout), change the language to Spanish.
3. You are redirected to https://docs.godotengine.org/es/4.x/ (note there is no html page specified anymore)

The same sort of thing happens when changing the version:

1. Go to https://docs.godotengine.org/en/stable/about/list_of_features.html
2. From the pulldown at the bottom of the left sidebar (not the flyout), change the version to latest.
3. You are redirected to https://docs.godotengine.org/en/latest/ (note there is no html page specified anymore)

[rdswift]

I just realized that perhaps I should have reported this on the https://github.com/readthedocs/sphinx_rtd_theme repository instead.

EDIT: I see that it has already been reported in readthedocs/sphinx_rtd_theme#1628 and readthedocs/sphinx_rtd_theme#1638. Sorry for duplicating it here.

[humitos]

Yeah, the issue you are reporting is related to the Sphinx theme. We've changed/deprecated the flyout from there in favor of the new flyout (bottom on the right)