Use fill="none" for fill="#fff" for background color

[shinokada]

These days developers use dark/light/system modes. If you have fill="#fff", you have the white bg when the mode is dark.

For example, bluesky has it.

// this line
<path d="m0 0H512V512H0" fill="#fff" />
// to 
<path d="m0 0H512V512H0" fill="none" />
// or
<path d="m0 0H512V512H0" fill="transparent" />

[edent]

That's an interesting idea. Could you please show a screenshot comparing them?

[shinokada]

The following screenshots are on the dark mode.

With fill="none"

With fill="#fff"

[edent]

Looks good. Are there any icons where the background colour forms part of the logo?

[shinokada]

There are many SVG icons have <path d="m0 0H512V512H0" fill="#fff" />.

https://github.com/edent/SuperTinyIcons/tree/master/images/svg

You can see all the icons at https://svelte-supertiny.codewithshin.com/icons. You will find may icons have white background.