[css-forms] Mechanism to influence the localisation for temporal controls?

[lukewarlow]

It's been discusssed that we don't want to give authors individual control over the ordering of field-components and field-separators due to the internationalisation requirements. While this is understandable, is it potentially desirable to allow authors to override the chosen locale?

For example, I can set the html document's lang to en-GB but the date input still takes the OS/browser locale for deciding the order of the input.

Should we allow overriding this via e.g. a locale attribute or something?

I know this is probably more of a HTML discussion but figured I'd open it here to keep css-forms issues together for now.

[lukewarlow]

cc @annevk I think this is potentially relevant for the discussion we had around HTML-in-canvas and how controls should probably use page locale not OS.

[annevk]

Yeah, see whatwg/html#10437. The lang attribute suffices and I think we should just make this change.