Font, size, mark colour and block attributes all answer the same question — the
one value the selection agrees on, blank when it mixes. One `uniform` walk now
serves all four, framework-free, so any chrome can read it inside its own
reactive wrapper.
The classic toolbar keeps its own copies for now: it is the baseline the ribbon
is compared against, and it should adopt these only once that comparison ends.
Steffen Becker
f7ee9546a4