theme PoofWindow with CSS

[Danielle Foré]

Like the spinner in gtk, we should probably be theming the poofwindow (the neato poofy cloud animation when you DnD something into the void) from CSS so that the theme/gtk controls the animation speed, amount of frames, etc. I imagine that should reduce a lot of code complexity there.

For reference, the spinner theme CSS looks like this:

@keyframes spinner {
    0% { background-image: url("assets/spinner-01.svg"); }
    14% { background-image: url("assets/spinner-02.svg"); }
    28% { background-image: url("assets/spinner-03.svg"); }
    42% { background-image: url("assets/spinner-04.svg"); }
    56% { background-image: url("assets/spinner-05.svg"); }
    70% { background-image: url("assets/spinner-06.svg"); }
    84% { background-image: url("assets/spinner-07.svg"); }
    100% { background-image: url("assets/spinner-08.svg"); }
}

.spinner {
    background-color: transparent;
    background-image: url("assets/spinner-01.svg");
    background-repeat: no-repeat;
    background-position: center;
}

.spinner:active {
    background-image: url("assets/spinner-01.svg");
    animation: spinner 600ms infinite linear;
}

[Aneurin Hall (aneurin-hall)]

I think that now that this is getting a code review it might be a good time to speak up. For me the fact that the "poof" effect apes an outdated and inherited idiom from a certain fruity desktop is reason enough to nuke it from space. The cartoony effect looks out of place in a desktop focused on clean design and elegance. Now that pantheon's notifications have a set of modern and appealing animations the inconsistency has become even more dramatic. I believe that the notification appearance animation (reversed and tweaked) provides a template for a more appealing effect.

[Danielle Foré (danrabbit)]

Going to mark as "won't fix" for Files since it should use LibPlank