What?

Just adding some fancy animations to Firefox's boring static movements

<aside> ❤️ Notable Help: u/poorman3333 & u/It_Was_The_Other_Guy

</aside>

Make Hovering Over Inactive Tabs Have A Small Fade In Animation

Yea.

/* Makes Hovering Over Inactive Tabs Have A Small Fade In */
/* Thanks u/poorman3333 */
.tabbrowser-tab:hover > .tab-stack > .tab-background:not([selected="true"]) {
    transition: 300ms !important;
}

Pin / Un-Pin Tab Animation

Makes pinning and un-pinning tabs have a small growth animation since Firefox just snaps them into place while no other browser does.

/* Pin / Un-Pin Tab Animation    */
/* Thanks u/It_Was_The_Other_Guy */
.tabbrowser-tab[fadein]{transition: min-width 250ms linear, max-width 250ms linear !important;}

Toolbar Button Fade In Animations

Adds Chromium-like fade in animations to whenever you hover on any button in the Toolbar.

/* Toolbar Button Fade In Animations */
/* Thanks u/9hp71n */

/* Shield Icon */
#tracking-protection-icon-container:not([disabled="true"], [checked], [open], :active),

/* Lock Icon */
#identity-icon-box:not([disabled="true"], [checked], [open], :active),

/* Extentions & Menu Button */
toolbar .toolbarbutton-badge-stack:not([disabled="true"], [checked], [open], :active),

/* Back / Forward / Refresh */
toolbar .toolbarbutton-1:not([disabled="true"], [checked], [open], :active) > .toolbarbutton-icon,

/* Star / Bookmark Button */
.urlbar-page-action, #urlbar-go-button, .search-go-button:not([disabled="true"], [checked], [open], :active) {
    transition:background linear 250ms;
}