I'm trying to create a PDF from PowerPoint where some lines have a "Glow" effect in order to make them more visible against the background, like this:

However, when printing to PDF, the transparency that comes with this "Glow" effect in PowerPoint seems to be flattened somehow, by creating a relatively coarse bitmap overlay which looks like this:

I can't seem to find a way how to convert this PowerPoint file such that the transparency is retained in the resulting PDF, or at least such that the background shape is not getting pixelated.
I attach both files for testing.
Thanks for all ideas.
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