Explain these Colab warnings for my valid SVG code-CodePudding

I put the following code into a code cell in Google Colab:

%%svg
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg width="400" height="110">
  <rect width="300" height="100" style="fill:rgb(100,100,255); stroke-width:3; stroke:rgb(0,0,0)" />
</svg>

The result is properly executed and rendered but the code itself is embellished with red markings at the beginning of each tag and there is a red vertical line at the right border of the cell to indicate some warnings.

The code itself has been validated by

CodePudding user response：

You are missing the namespace: xmlns="http://www.w3.org/2000/svg" in the root element (<svg>).

A SVG document is a XML document, which is a general markup language. The application that reads the file/document needs to know what "language" the element uses.

<?xml version="1.0" encoding="UTF-8" ?>
<svg xmlns="http://www.w3.org/2000/svg" width="400" height="110">
  <rect width="300" height="100" style="fill:rgb(100,100,255); stroke-width:3; stroke:rgb(0,0,0)" />
</svg>

CodePudding user response：

The red markings are gone now. It was only a Colab bug after they introduced a new feature highlighting syntax issues. This new feature treated the code as written in Python.