Core i5-520Mなんて化石時代のIntel HD GraphicsとWin10提供のインボックスドライバーの組み合わせでも問題なく3D表示される

https://support.google.com/maps/answer/3031966?hl=ja
より
https://www.khronos.org/webgl/wiki/BlacklistsAndWhitelists
> Firefox on Windows
> For WebGL in Firefox on Windows, Windows XP or newer is required. The following minimal driver versions are required: either NVIDIA >= 257.21, or ATI/AMD >= 10.6, or Intel driver versions from September 2010 or newer.

> Firefox on Mac OS X
> For WebGL in Firefox on Mac, Mac OS 10.6 or newer is required.

> Firefox on X11
> In Firefox 4 and 5 on X11, only the NVIDIA driver is whitelisted.
> In Firefox 6 and newer on X11, the following minimal versions are required: either Mesa >= 7.10.3 (or Mesa >= 8.0 for the Nouveau driver), or NVIDIA >= 257.21, or any version of FGLRX implementing OpenGL 3.0 or newer (but FGLRX is blacklisted when the Linux kernel version is 2.6.32)

> Firefox Mobile
> Firefox Mobile is not currently using any blacklist for WebGL.

とりあえず
https://get.webgl.org/
でWebGL動くか確認