Restore container icon fill - Icons should not be just outlines

[mirzmaster]

Container icons in context menu used to be solid and with the redesign they're not just outlines, making the colour much more difficult to discern.

(looks large here, much smaller in practice making it even harder to discern)

Visually, I used to navigate this primarily by colour, but now I have to confirm the name. I didn't realize how reliant I was on the colour fill until it was gone. This is a regression in usability and accessibility.

[kelimuttu]

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