浏览器白色主题下，收藏夹网页图标辨识度很低。

[Steve Sun]

Is your feature request related to a problem? Please describe.

系统环境：Windows 10 22H2
浏览器：Firefox 124.0.2 (64-bit)

Describe the solution you'd like

把favicon中透明部分换成不透明的颜色。

Additional context
感谢做出这么方便的工具。