(Whichever category first claims the namespace will own that namespace, and even if you get to choose between multiple options in the drop-down, the resulting link will always point to the “dominating” category.)
And it’s not such an unlikely scenario. A multilingual forum for instance could have /c/english/support and /c/english/support.
@riking’s suggestion of adding colors would help a lot, but I think it’d be best if also the complete path of the sub-category was shown in the hastag, e.g. #english:support
I think this use case needs to be solved before we throw tags into the mix.
Very nice
With the addition of Topic mentions (and autocomplete), making interconnected wikis will be much nicer!
Thought: Discoverability @mentions are easy to understand, because the @ appears in the styled text. If I #mention a category, it hides the #. I foresee lots of “how did you do that?” posts, or worse: people not using the feature because they don’t know how.
If I mention howto, the link is https://meta.discourse.org/c/10-howto whereas if I mention #howto:tips-and-tricks, the link is https://meta.discourse.org/c/howto/tips-and-tricks/45.
If I follow the former, the “10-” in the link remains, while in the latter the “/45” is cleaned out.
Any good reason for this discrepancy? I like my URLs clean
https://meta.discourse.org/c/10-howto is a supported URL and I believe https://meta.discourse.org/c/howto/10 was never implemented because it’ll clash with the routes of child categories. Is the 10 an id or a category name?
The other link is actually a redirect which is why /45 is removed from the route.
Also another feature that I sneaked in unintentionally/intentionally is with regards to how read restricted categories are displayed to users. Instead of decorating the link, read restricted categories will appear as normal text for users who do not have the permission to view the category.
I did not object to the plain-URL rendering form, so I don’t have strong feelings here.
Some thoughts:
we spend a lot of time educating people about categories and it is nice to tie the visual styles together to reinforce that.
#categories will naturally get mentioned a lot less than @usernames, so having a more “energetic” rendering style isn’t a big deal.
when we bring tags under the same namespace, that means it will have two different rendering styles, so perhaps @mcwumbly is right on this long term. Simple is good.
I do believe rendering the hash is important otherwise people will not learn how to type these mentions without special effort
I lean towards “let’s just use the plain URL form for now”, particularly if we want to unify the tag namespace…
Just implemented it 
