Agree

I guess giving it the same colour as the words in the filters would fit.
I.e. #444 instead of #999

.j-toggle-sidebar-header {
    border-bottom: 1px solid #eee;
    border-top: 1px solid #d3d3d3;
    color: #444;
    margin: -11px 0 7px;
    padding: 10px 0 10px 19px;
}

Color #444 makes word 'Sidebar' too much like links below. Maybe bigger/bold (or without this word at all).

@javigomez I had used the same color HEX as for the footer status as an not-link label. (and issue with contrast in status bar too!).

But, i agree on working on standard colors for future admin template, which would be required as standard rules to follow (as it is existing now for code standards, and language strings) ;-)

See: #6340 (comment)

Do we even need this text? Having it is a bit like adding a label to the menu to say it is a menu. Does it serve a purpose?

That's what I said in the comment: #6340 (comment)

If it's ok, I can add the removal of the title in the no-gradient PR #6340
But that PR is getting larger and larger...

@nonumber yes, but with removal of title, your PR will be ready to commit, and with this PR ready to be closed too! ;-)
So

I think this can get closed in favour of #6340
(if that gets in ;) )

Closing as #6340 was merged