I can look at a single category. Or I can look at all the categories. Is there a way to look at all the categories sans specified ones. For instance, if I didn’t want to see “Developer”, “Showcase”, and “Meta” ?
Otherwise, I don’t see that the categories have much point. Looking at one category at a time is impracticable. Which leaves you looking at all categories.
Thanks!
You can “mute” categories in Preferences/Categories.
Thanks! That was really buried. Is this something everyone already knows? Supposed to know? I wonder how many people are using this feature.
I’d say anything that isn’t coming to the home page is an “advanced” feature of any forum. Assume no one knows anything or changes the default settings is probably a reasonable assumption 
People who use a forum for a while gradually get into other features.
You can also do the same with tags, BTW.
e.g. You could choose to “mute” the Discourse tag: https://talk.tiddlywiki.org/tag/discourse – use the “bell” in the top right to choose what kind of notifications you want.
This is also available in Preferences > Notifications > Tags where you can see all your category / tag notification settings.
The posts tagged with #notifications have various other descriptions.
What got me thinking about this was Saq’s concern that his GitHub project not just be in the developers’ section. I was wondering if it made much difference, if most people are viewing everything anyways.
You’d really have to trust that all the tags were used correctly, or at least the way you imagined they would be used.
The main thing is, these settings are buried pretty deeply. So you would have to be really committed to never seeing tag #notifications again to bother setting them. I’m surprised they don’t have some simpler, quicker way to make the settings.
Many of these are for either very large / high volume forums, and for giving users abuse filtering tools directly.
The quicker way is directly on the tag or category pages.
I’d say per post notifications are most heavily used.