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kotlinlang

Why the console displays this: Failed to create DirectX12 device.

Typically it's because you don't have your graphics card drivers properly installed / your system doesn't support directx.  Compose will fallback to an alternative rendering mode (like software rendering) in such cases, so you can usually safely ignore this message, but if you are running into graphics-related bugs then this is useful information (the fact it failed to initialize directx) to include in your bug report so we know what rendering technology we should be looking at.

```as I understand it, because of this, when resizing a window, redrawing is very slow```


Correct, software rendering is much slower than hardware accelerated rendering. But if you have a user who happens to run an app on a computer with improperly installed graphics drivers, there is not a whole lot you as the application author can do about that, you mostly just let the system do the best it can despite it being a little slower.  Not substantially different from a user trying to run your application on a super old/slow computer, it just means the program runs slower.