When the note spacing is tight, Dorico apparently doesn’t take tremolo slashes into account when calculating the “tuckability” of notes. The screenshot is from Galley view by the way, so there’s no other excuse 
Galley view isn’t a good place to look for this, since there is also no justification in galley view; you would need to have an extraordinarily full system for there to be insufficient leftover space in the system for these collisions to be avoided by the usual means of justification. It’s not a bug, in any case, since Dorico is not designed to consider the width of tremolo strokes on the stem when performing note spacing; it’s not, however, an unreasonable thing to expect and it is possible that we might take tremolos into account for spacing when we return to the area of enriching the kinds of stem decorations you can produce in future versions.
Hi Daniel, thanks for your reply. Attached is a bit of the same passage in Page view. The issue starts to manifest itself when the “Default space for crotchet” value is set to 3 3/4 spaces, just slightly tighter than the default. No manual spacing adjustments were made, and according to the readout the system is 99.2% full at these settings—pushing it, but not “extraordinarily”. Probably, resolving the multiple near-collisions with the tremolo strokes would neatly account for the remaining 0.8%. I’ll admit, maybe the term bug was poorly chosen, sorry about that. Let’s call it an unforeseen edge case. As always, I delight in those, even when it takes a couple days of copying out Scriabin to find one.
