Wrong color layer when exporting to PDF

Hello !

So I am using Figma to create slides for a presentation, I made this nice shape against a blue background and used the Lighten layer mode to be in the perfect color.

But the moment I export it to PDF, the shapes show in the PDF slides as with their normal color, instead of with the Lighten layer mode. Is this a bug? Or am I doing it wrong? How can I export these slides so the shape shows in the color I intend it to be (using Lighten layer mode), and not its “Normal” layer mode color ?
bug