There are a number of icons that have not been part of M229, which currently reside in VE, that need to be aligned to our icon guidelines:
Even though they were scaled to be size-wise aligned in T190151, they might miss things like stroke-width, etc.
“References list” icon is part of T177847
@Esanders has been working on some (e.g. https://gerrit.wikimedia.org/r/#/c/421354/ for Score icon).
I would say they're good enough now:
I'm calling this one done since we've made improvements.
@Volker_E If there are further changes you'd like, please feel free to file a supplementary task. :-)