I assume the default colour space for Inkscape is sRGB but I have noticed that if I create some basic vector shapes in Inkscape and fill them with colours, then I open Adobe Illustrator, make sure that's in sRGB and create the same shapes (same RGB settings) that the colours are actually slightly different. It's most noticeable with greens and to some extents reds. If I take a screenshot and get the RGB values of the "same" colours in the two programs then the RGB values are not the same, so there's definitely a difference (it's not just my eyes).
I would have thought sRGB would be the same no matter which program was using it, i.e. an RGB value of "x,y,z" should display the same colour as it's from the same colour space?