Steps to reproduce:
1. Create object that crosses page edge and give it some effect (e.g. dropped shadow).
2. Save as PDF, choose "Rasterize filter effects" and set Bleed to 5 mm.
Result:
The object and the effect are rasterized and visible in the PDF, but they are cropped by the page size. The bleed area is empty.
Expected result:
The object and the effect should be visible in the page and bleed area.
Additional notes:
* Objects that don't get rasterized are visible in the bleed area.
* The same problem happens if you select "Use exported object's size" and try to export object crossing page boundary.
Analysis:
The function sp_asbitmap_render in src/extension/internal/cairo-render.cpp always limits the bounding box to the document size. This is incorrect if we are saving different area:
Geom::Rect docrect(Geom::Rect(Geom::Point(0, 0), item->document->getDimensions()));
bbox &= docrect;
Removing those two lines fixes the problem, but is probably not the best fix. Correct fix would be to use the actual bounding box that is calculated inside CairoRenderer::setupDocument, but doesn't seem to be saved anywhere. I am not familiar with inkscape code enough to suggest a good fix.
This looks to apply to ANY object with ANY filter applied to it. I've tried a dozen different filters (drop shadow, blend, etc) and they all end up with the same result.