Mark Jaquith

<ol>
<li>Check a category.</li>
<li>Uncheck “Uncategorized”.</li>
<li>Mutter “stupid ‘Uncategorized'” under your breath.</li>
</ol>
Sound familiar? With this stupidly simple plugin, you just have to do the first step. When you check a category and the default category was the only thing checked before you clicked, it’ll uncheck the default category for you. Boom.

Categorized

Unchecks the default post category when you first select a non-default category

Masahiro NAKASHIMA

This plugin can change bottom to “Admin Bar”. 
It also can change Admin Bar position with “shift + up” or “shift + down”.
管理バーの位置を下に表示することが出来ます。 
また、「Shift + ↑」「Shift + ↓」で上下に位置を変えることも可能です。

Admin Bar Position

Thanks. It is very usefull!

If you ok, please update something.
Because plugin page displayed caution message.ｈ

Nice tiny function! Thanks

Hover on native button are not working at all..
Instead use this updated and working plugin :

https://wordpress.org/plugins/bottom-admin-toolbar/

Buggy extension

This plugin can change bottom to "Admin Bar".

Categorized vs Admin Bar Position