I just implemented automatically adding deep links for com.unity.packagename blocks in my site (see example), but if I was to manually post the same link here:
The link doesn’t work, the href has been stripped. Could we allow deep linking?
Whitelisting the links that might be used could be an option:
com.unity3d.kharma:
unityhub:
This could also be useful for staff in future when the forums are migrated here, so they can link to releases in their announcement posts.
Well, custom URL schemes are always a potential security risk which is probably the reason why they are blocked by default. On my machine I recently played around with custom URL schemes and created my own “B83:” 
I’m sure such a link would also be blocked. I just tried it and even the preview already stripped my link.
So custom URL schemes probably have to explicitly be allowed. Not sure if this discussion software provides some kind of whitelists for things like that. Though I agree that such links should be supported.
Note that some “unusual” URL schemes like mailto: seems to work here. So there has to be some kind of whitelist I guess.
That is exactly the case with Discourse; non-standard URL schemes must be explicitly allowed in the app settings.
I’ll add the unityhub:// scheme to the feature list.
Though, I cannot imagine all custom URLs can be safely supported.
Just whitelisting these two is all I’m really looking for, thanks!
Make sure you also get the kharma package manager one as that’s the one I’ll likely be using often