The issue before was that the left sidebar would become too tall for
the screen because the standard header that has “STREAMS” and buttons
is 20px tall, and this one is 30px tall. This makes it much shorter,
changes the text to be the same style as the “STREAMS” text (medium
grey, uppercase text).
The markup is then fixed to be significantly less verbose than before —
changing a list to just a simple link.
This system hasn't been in active use for several years, and had some
problems with it's design. So it makes sense to just remove it to declutter
the codebase.
Fixes#5655.
This restructures the <a> tag to be clickable essentially anywhere
within the <li> tags, unlike before where due to it being “inline”, you
had to hover over the text in particular.