The discussion revolves around setting a default category in the ‘Create Topic’ dialogue on Discourse. hiro_s initially seeks to have the ‘General’ category pre-selected when creating a new topic, noting that it currently defaults to a different category. Alexander directs them to a solution via the default-composer-category-component plugin. hiro_s clarifies their intent: they want the category to pre-populate based on the current category context, such as when creating a topic from the ‘Underground’ category, it should default to ‘Underground’. merefield corrects a misunderstanding, pointing out that the ‘New Topic’ button on the topic page already defaults to the current category, but hiro_s confirms they are referring to the root level (Discovery Topic List). merefield suggests disabling the uncategorized category, which hiro_s confirms they’ve done. nathank reaffirms that the plugin can achieve the desired behavior. hiro_s concludes by thanking the community for their help.
Hi 
! Welcome to Discourse Meta 
!
I think this can be useful for you
Thank you Alexander! I will give this a try and let you know!
I’ve had a while to ponder this further, and I’d like to add a bit of clarification.
I’d like for the category to be ‘pre-populated’ depending on what topic the user is already in.
Here is an example of a Discourse forum where this is happening:
So if the user is in the Underground category and they press ‘Create Topic’, ‘Underground’ will be pre-populated in the Create Topic dialogue. And if they were in the Otherground category, then THAT would be pre-populated.
But there is no New Topic button on the Topic screen?
I think this may be in the works with the changes to Uncategorized and General. Not sure on the exact timeline but I think it’s on the horizon. 
that’s the Discovery Topic List, not the Topic route (oh you deleted the Post?!)
There is no “New Topic” button on the Topic screen: just scroll up here! (this is a Topic screen after all).
This is a screenshot of the Discovery Topic List, not the Topic screen.
What I believe you want is already implemented.
For example, if I am in Contribute > Bug and create a Topic, it’s preset with the Contribute > Bug Category:
Yes @merefield I believe that I was incorrect in the way that I described it earlier. The latest post most accurately reflects what I want.
What you referred to as the ‘Discovery Topic List’ is the root level of my forum. And when ‘New Topic’ is pressed, I want it to default to General, as per screenshot above.
I was clumsy in my wording, I apologize.
Yes I had done that already, thank you! re: allow uncategorized
So with all of the information I’ve gained in this thread (thank you all), if I were to refine my question I think it would be thus:
Is it possible to set a default category (in the ‘Create Topic’ dialogue box) so that when the ‘New Topic’ button is pressed whilst on the ‘Discovery Topic List’ it is set to that default category automatically?
That TC mentioned above does this exact thing. Install it on your site and give it a go.
Yes Nathan you are correct. Thank you all, particularly @Alexander!
you might consider turning this off: