Comment 6 for bug 872572

There are two separate issues that need to be addressed:

The first is that it is not clear from the CSS and SVG specs what the correct behavior should be. What should cause stand-alone forms to be shown? Changing font size? Changing font weight? Adding letter spacing? Moving characters using the 'x' or 'dx' attributes? The latter does result according to the specs in breaking non-mandatory ligatures.

The second issue is the amount of code that would need to be rewritten. Currently Inkscape handles text one tspan at a time. As any change in color results in a new tspan, Inkscape would have to be change to handle multiple tspans together. Pango does have a function that is designed to shape text across changes in style (pango_shape_full())[1] but it would still require quite a bit of code rewriting. I am hesitant to try to make any changes until the first issue is settled.

[1] https://developer.gnome.org/pango/stable/pango-Text-Processing.html#pango-shape-full