Board Thread:Watercooler/@comment-24520859-20171121124441/@comment-1117661-20171125220444

Using the root page for the base template too sounds like a great idea. Only drawback I see is it's a bit fiddly with the preview when editing the base template, though it not that big of a hassle. A comment with a tip about it should be enough for the most part I think. Like: Contents that would usually be on PAGENAME/base
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As for the  links it's no problem. I remade Module:Languages so it's easy to add other formatting methods. One that adds displays uselang links instead of generated bluelinks, while leaving redlinks intact, is no problem. And can be built-in into LangSelect (which in fact just invokes another formatting method of M:Languages).

I'm not sure templates as subpages are viable. You have to keep in mind that LangSelect uses a DPL query to get list of subpages. Making templates use this system is no problem (just add  parameter to the invoke), but it'll will run a query for each one, to see what langs are available (this can be cached, though). Having LangSelect won't work with base template on the same page as both would have to be includable (or we could have a template to invoke such templates)
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LangSwitch should do the better job here. Combining it with variables would allow for cleaner code with all strings defined at the template start.

LangSwitch also has the  parameter that can also be combined with a variable. So instead of having to add  in every template used on a Polish page, there could simply be a   at the top, and all instances of LangSwitch will use that language or its fallback. Off course that variable can be built into LangSelect.

When it comes common translations, it might be worth checking out, but I'm not sure we'd get many that are context-independent. Stuff like infobox labels etc. can work, but I wouldn't count much on anything beyond basics.

It's a useful template, but as Kocka said, it becomes redundant with base templates, and it seems that's the direction.
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