In order to export partly transparent symbology to PDF in QGIS as vectors, the symbology itself needs to have transparency – if the whole layer is sat to be transparent, the symbology gets rasterized.
Having the symbology itself as transparent (which does export as vectors correctly), however, creates the effect of multiplying, increasing when elements overlap – up to a point where they no longer look transparent:
This is in stark contrast to having the layer itself as transparent, as below:
Unfortunately, however, this does not export as vectors. Is there a way to turn off multiplying of symbology transparency, getting the same effect as if the whole layer is transparent, in order to be able to export uniformed transparency as vectors?