Incidentally, on the same site above with the new sidebar, not only is the styling fixed to the box style but there’s a lock glyph on secured categories which I find a bit distracting. Also they are in alphabetical order and sub-categories are not displayed below the category they are in as you’d expect. In the screenshot below, “memories” is within “photos” and so should be displayed below it.
So, it is totally same than what old hamburger showed, and that wasn’t an issue to anyone 
There is now same trap coming up what WordPress has with its sidebar: a mile long scrolling.
oh yea the lock icon 
i really dislike the lock icon badge on anything for my users - to me the lock icon gives the impression of something being locked from them and i’ve had that complaint from users before. i used CSS to take it off my secure forums in the category page view and the drop down selector for that reason. and yes, to me it feels bit weird that there are icon control options for the other customizable sections of the menu, but not the categories section. 
I’m not so fond of the lock icons either, but do think it’s important to distinguish the secure categories in some way visually. How else would you suggest we do it if not with a lock? At least in the sidebar it is small… in other places the lock is huge. Here’s how it looks on the category page on my neighborhood forum:
Are you suggesting that we make the icons customizable in the categories section too? Not sure I am in favor of that change. It could become a cluttered mess on many sites. For now the colors have a purpose.
This has now been fixed as of my post above. The ordering is still custom but sub-categories are displayed under the category they are within. One thing I still would love to see in the sidebar is the ability to open/close categories with sub-categories, because the list can get quite long.
where possible i hide things from users that can’t access them, unless i want to entice them or something. thus, i’d rather no lock and only links they have access to. IMHO, the lock appearing on a category they have access to generally gives users the visual impression they don’t have immediate access to it. i don’t need to show the lock icon, just the access itself. my point is, for users that have access to a secure category, they don’t need to see the lock. i indicate in category descriptions that categories are secure. i find the lock misleading. unlocked is also an unlocked icon, not a lock icon. 
That’s a good point… though I still think in many communities people will want to know if the category is public or secure. I also think people like to know who else has access.
Maybe the visual could be handled differently in the sidebar… eg only show the lock when the mouse cursor is over the link, or show a little popup that indicates it is secure and which groups have access.
exactly this! i like it.
just note that i am super picky when it comes to UI stuff lol 
And then we save some space and change UI on larger screens but we miss mobiles that are larger used today than desktops.
And what is that purpose?
I also find it distracting because it suggests inaccessibility - and the lock icon is being used with two different meanings: for closed topics and for “private” i.e. “non public” categories which is confusing. So confusing and distracting: not good.
The categories that are not public that you cannot access are invisible, so they don’t need an icon.
So the icon for a non-public category that you can access should indicate two things:
So how about… 
Not on my forum
I know, I know. I’ve changed that behaviour 
So, I totally agree you — it is a bit strange to show an informative icon that can’t be seen in the meaning that should be visible to those who can’t see it.
So, open lock is quite good remainder for users that they are on place that has limited access.
I wouldn’t use any icon, though.
(I can’t remember any more what was the issue in the first place… what ever as our teens say)
I believe this was one of the proposals in the previous topic Pick different icons for 'closed topic' and 'secure category'. Though judging from the back and forth in there it seems there was no clear-cut universal option that would please everyone. I think someone also made the point that, having been this way for so long, it may be surprising for some forums to suddenly have all their private-category locks unlocked/removed even if the change is ultimately only visual.
It is interesting that so many people have encountered this issue though. Based on the previous topic, I don’t know if it’ll ever be possible to make a core change (possibly only for new sites?), but knowing what alternatives people have attempted for their own sites is probably useful for anyone facing a similar conundrum.
I think using the Category Icons component has been the advice so far if you don’t want the padlock icon on your secure categories, and having it working with the new sidebar should make that possible again. 
(and the padlocks will be even easier to swop out when it makes it into core 
)
i remember coding HTML back in '92 and being happy when we were able make a bullet list of links 
You were early to the party
The lock-open icon gives a sense of imbalance. So why not unlock icon…?
there is also the key icon 
I made a really scientifically accurate study and asked opinion of my few active users and of my friends who aren’t on my forum. Any of them are aren’t IT/web-professionals, but ordinary end users.
Any of them didn’t even understand point of such icon and they had hard time to understand whole question. I suppose it is because such system isn’t in use anywhere that is familiar for them, aka. social media. If you are a member or otherwise allowed you can see content, if you aren’t… well, you can’t see. Like everywhere.
So, the issue of padlock-what-ever icons must rise from admins’ need to advertize. Then there is need to show some indicator (like paywalls should do when sharing links) only when such closed or limited topics or categories are visible on heading level. But that is the only reason and then what ever mark works.
This isn’t a general UX topic anymore, if even has been. This is topic of how closed and paywalled forums should warn theirs random users not to make unnecessary clicks. Another edge case.
the more i think about this, the more i believe the badge for a secure forum should be optional, and i think from a logical perspective, it should also be a key not a lock (as in, the user has the key to get in). yesterday i was doing some work on the component i use to control the sidebar and i enabled the lock badge on my lounge for about an hour and immediately users were confused thinking it was locked, and certainly the fact the lock badge just appeared was a big factor. but that badge is misleading. i keep it on staff categories so staff have an extra indicator they are in their private categories, but users can’t see those ones anyways. i’ve set my Lounge so my anon users can’t see it, so the locked badge doesn’t make sense to me. i’ve hidden it for the Lounge in every other place as well (badge-wrappers, category headers). i think if an option to show a secured category to users is necessary, it should be the key icon badge.
i also feel like the category bullets in the sidebar should adhere to the category style setting if it is set to “none”.
