WEBGL_debug_renderer_info is deprecated in Firefox and will be removed. Please use RENDERER.

[jjant]

This snippet makes Firefox give the warning in the title:

glow/src/web_sys.rs

Lines 218 to 221 in 7e702f6

	webgl_debug_renderer_info: get_extension::<web_sys::WebglDebugRendererInfo>(
	&$context,
	"WEBGL_debug_renderer_info",
	),

I'm not sure about how glow uses that information (if it does at all), but it looks like you can use ctx.getParameter(ctx.RENDERER) to get something similar:
https://stackoverflow.com/questions/69055946/what-does-the-message-webgl-debug-renderer-info-is-deprecated-in-firefox-and-wi