um, this isn’t svg loading from spritesheet which was the PR I submitted. 
I went ahead and fixed: https://www.babylonjs-playground.com/#664QM9#2
- Uncomment line 20 to remove white square around the button.
- This svg image is created using code instead of a svg image editor. Therefore, in order to find out the sourceLeft and sourceTop, I had to reopen the file in inkscape and figure out the actual image coordinates which is somewhere around 42 with width/height of 75.
- You may or may not see the icon depending on your monitor resolution because 75*11 was what worked on my screen. You may have to play with the values to get it to display in yours. One major caveat of creating svg from code and loading it is that its size is often dependent on screen res. In the first image below, the icon is displayed normally. When the window is resized, the svg icon shrinks.
If your use case involves multiple svg icons, you can use batch loading of svg assets. The demo is here: Babylon.js Playground
Hope it helps !