Could not apply XXX image style to public://images/XXX.svg because the style does not support it.

We're seeing this, too. In our case, we've got:

1. A Paragraph type that includes an entity reference field to a Media entity (image).
2. The image field on the Media entity allows the following extensions: png, gif, jpg, jpeg, svg
3. The display of the Paragraph type uses the "Thumbnail" format with an image style.

When a node that includes an instance of this Paragraph type is viewed, the SVG is correctly shown, but we get a warning like this in the logs:

Could not apply XXX image style to public://my-icon.svg because the style does not support it.

Heh. Just noticed that this issue is 6+ years old!

Looking at the code in image.module, it calls $style->supportsUri($variables['uri']) to see if the image type is supported. If not, it just returns the original image then logs the warning. Given that the image is displaying, I don't think there's anything this module can do about it.

Work on this warning was in #2652138: Image styles do not play nicely with SVGs → . Would be nice to suppress this warning so it doesn't fill up the logs, but I don't think that's this module's problem.