Custom Post Types with SVG menu icon
To use SVG icons for your Custom Post Types in WordPress, encode the SVG in base64. Make sure that your SVG includes currentColor to match the WordPress menu.
register_post_type(
'product',
[
'menu_icon' =>
'data:image/svg+xml;base64,' .
base64_encode(
'<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="currentColor"><path d="M11.644 1.59a.75.75 0 0 1 .712 0l9.75 5.25a.75.75 0 0 1 0 1.32l-9.75 5.25a.75.75 0 0 1-.712 0l-9.75-5.25a.75.75 0 0 1 0-1.32l9.75-5.25z"/><path d="m3.265 10.602 7.668 4.129a2.25 2.25 0 0 0 2.134 0l7.668-4.13 1.37.739a.75.75 0 0 1 0 1.32l-9.75 5.25a.75.75 0 0 1-.71 0l-9.75-5.25a.75.75 0 0 1 0-1.32l1.37-.738z"/><path d="m10.933 19.231-7.668-4.13-1.37.739a.75.75 0 0 0 0 1.32l9.75 5.25c.221.12.489.12.71 0l9.75-5.25a.75.75 0 0 0 0-1.32l-1.37-.738-7.668 4.13a2.25 2.25 0 0 1-2.134-.001z"/></svg>'
),
],
);