Spinny ball "working" icon
When you're doing stuff the spinning ball animated gif appears. We should do this with animated svg.
@field2 Can you link me a screenshot of the gif and possibly the location on where I can find it in the core? I'd like to tackle this if I could.
spinner.gif is in src/wp-admin/images/spinner.gif and spinner-2x.gif

@field2 Here is my version using CSS. No SVG or gif needed.
http://codepen.io/grayghostvisuals/pen/ogLemL?editors=0100

or http://codepen.io/empireoflight/pen/XNpzOw?editors=1100 ?
@field2 What are your thoughts about my original demo? I can certainly slow it down which is what i think your demo is doing
The main thing is the size is off-it should be 18x18. Other than that it's fine I think.
ok 18 x 18 is all I need to know. standby
@field2 I'm trying to find all the instances of this spinner and so far this is what I've found…
wp-admin/customize.php
wp-admin/css/common.css
wp-admin/css/customize-controls.css
So far this is this list that makes sense but I've also found a few lines in common.css that are intriguing…
body.about-php #TB_window.thickbox-loading:before,
body.plugin-install-php #TB_window.thickbox-loading:before,
body.import-php #TB_window.thickbox-loading:before,
body.plugins-php #TB_window.thickbox-loading:before,
body.update-core-php #TB_window.thickbox-loading:before,
body.index-php #TB_window.thickbox-loading:before {
content: "";
display: block;
width: 20px;
height: 20px;
position: absolute;
left: 50%;
top: 50%;
z-index: -1;
margin: -10px 0 0 -10px;
background: #fcfcfc url(../images/spinner.gif) no-repeat center;
-webkit-background-size: 20px 20px;
background-size: 20px 20px;
-webkit-transform: translateZ(0);
transform: translateZ(0);
}
@media print,
(-webkit-min-device-pixel-ratio: 1.25),
(min-resolution: 120dpi) {
body.about-php #TB_window.thickbox-loading:before,
body.plugin-install-php #TB_window.thickbox-loading:before,
body.import-php #TB_window.thickbox-loading:before,
body.plugins-php #TB_window.thickbox-loading:before,
body.update-core-php #TB_window.thickbox-loading:before,
body.index-php #TB_window.thickbox-loading:before {
background-image: url(../images/spinner-2x.gif);
}
}