musescore/MuseScore — pull request #1195 by MarcSabatella (2014-08-21 20:43:49+00:00)
Title: fix #29511: keep voltas when adding notes

I'm going with the cheap but hopefully safe fix: I keep spanners with MEASURE anchors, delete all others. It's probably possible to be more clever and detect if we are replacing the anchor note with another and keep hairpins & pedals if so, but not important to me right now.