Afaik, the browser will read GIF once and keep the bitmap in memory, then composite it into the right place when it needs it, which is a lot cheaper.
With SVG, the browser will render it once and keep a bitmap, then composite it.
With a CSS icon, there is no way for the browser to know that it's an icon at all. There is no clear delimitation between it and the rest of the page. The browser has no choice but to re-render it every single time.
Images or SVG are much better choices for icons than a bunch of CSS.
With SVG, the browser will render it once and keep a bitmap, then composite it.
With a CSS icon, there is no way for the browser to know that it's an icon at all. There is no clear delimitation between it and the rest of the page. The browser has no choice but to re-render it every single time.
Images or SVG are much better choices for icons than a bunch of CSS.