I guess it’s the vertical space available? When all controls fit right of the drop-down menu (“Latest” in your screenshot), then they align right. It’s because of the style declaration on that drop-down item:
But when they don’t fit, they occupy the next line and then just align left. It’s a small glitch, but I guess it could be fixed with a slightly different alignment declaration on navigation-controls?
The buttons share a common parent container, so they wrap as a single unit when there’s not enough space.
It looks like there’s some extra space around the new topic button here:
removing that might be enough to avoid it… wrapping these buttons is kind of a last resort, by default it only happens to admins on screens <355px wide, though factors like zoom levels and themes can affect this.
Maybe we could combine the admin and bulk select buttons here if they’re both present to avoid it