chrome.devtools extension panel icon doesn't look right

Question

setting a dev tool panel icon in chrome.devtools api from a png renderes offset and moves when I click it. the other stock icons darken when clicked - i assume this is an animation, i'm not sure why or how it's trying to animate my png.

how do i produce an image that will look right as a devtools panel icon?

Answer 1

Inspect the button image using another DevTools instance (all the images are stored in chrome-devtools://devtools/Images/toolbarIcons.png). In toolbarIcons.png, the normal and depressed (darkened) image versions are laid out in columns, so you should presumably do the same for your panel icon image.