Hi! I want to set custom splash screen for TMA, using feature, that announced here: https://telegram.org/blog/fullscreen-miniapps-and-more#loading-screen-customization

Here is my svg:

<?xml version="1.0" encoding="utf-8"?>
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
  <path d="M2,2 L8,2 L2,5 L8,5 L2,8 L8,8"/>
</svg>

I just took official example from BotFather and replaced path in svg (its correct path from here - https://svg-path-visualizer.netlify.app/#M2%2C2%20L8%2C2%20L2%2C5%20L8%2C5%20L2%2C8%20L8%2C8)

But BotFather refuses it:

What I do wrong?