Problems with the 'progress bars' when converting to PDF

[antiftw]

Like the title says, when using either of the mentioned third party sites to convert the page to a PDF the bars that indicate proficiency are not rendered properly

This is how it looks like on the webpage:

After rendering with Web2PdfConvert:

And with PDFlayer:

Like you can see, it's not completely broken, and both break in a slightly different way, but the bars are not drawn as they are supposed to be.

I've tried both the default and the print version, but they give similar results.

Any idea what could be causing this?