Add lang attribute that matches the currently selected language

[foxbunny]

Adds the lang attribute to the HTML element in the layout/indico_base.html and layout/base.html templates.

[tomasr8]

Should we use just the language or the full locale? e.g. en rather than en-GB? The region subtag is optional but maybe it's useful in some cases?

[foxbunny]

"Should we use just the language or the full locale?"

Script and region subtags are considered optional. See here:

https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/lang#language_tag_syntax

Having the language subtag is enough to pass the success criteria. Now, whether you would like to fine-tune it is up to you. It may be worthwhile to include a ui_language property on the current_locale object, so that this can be controlled from your end later, though.

[ThiefMaster]

We already have the moment_lang property, maybe we could add html_lang in a similar way?

[foxbunny]

We already have the moment_lang property, maybe we could add html_lang in a similar way?

Sure.

[ThiefMaster]

rst uses double backticks for code highlighting (single backticks are already used for rst references and similar features)