Created attachment 173100 [details]
SVG as exported from Impress (text redacted with Inkscape and saved as plain SVG)

To reproduce:

* In Impress, draw a few shapes with a colored background, and assign them different levels of transparency.
* Select the shapes on the slide and export them to SVG.
* Open the resulting SVG in Draw, or import it into Writer (any other LO app should yield the same result but was not tried), and examine the semitransparent shapes.


Expected result:

All drawing objects look just like they did in the original Impress presentation.


Actual result:

Transparency values differ from the original when opened or imported in LO.


Additional information:

Transparency is as expected when opening the exported SVG with Inkscape. Apparently the error happens on import.

I did not investigate further how different transparencies are affected (e.g. inverted, offset by a certain value, scaled etc.), or if documents generated in an external SVG application behave the same. Opening the exported SVG in Inkscape and saving it (as plain SVG) does not seem to have an effect, though (rendering issues are the same as with the original exported SVG).

The bug was observed with 7.0.5.2 on Windows 10; I did not try any other versions.