There are two ways to link to Mozilla Support articles. Which method you use depends on where you are linking from. If it's from the chrome of Firefox or Firefox for Android, you'll want to use the "in-product" method. If you are linking from a web property, then the URL minus the locale string is the way to go. Here's how they work.
The last part of the URL, the topic, can be any string.
Firefox for Android links should use /1/mobile to distinguish the product.
The tuple (product, version, os, locale, topic) determines where the user actually goes. This allows the SUMO team to change the target of the Help button without breaking links/buttons in Firefox. We have specific targets for all the topic values, and sometimes we can split apart users from OS X or Windows to the most relevant articles, or those with old/specific versions of Firefox, etc.
Link to SUMO from a web property
If this content is being served via the web and is not shipped with the browser, you don't need to (and shouldn't) use the in-product links.
All you have to do is use the URL without the locale string. SUMO will automatically send the user to the version of the article in their language.