Problems with some combining diacritics (macron, breve, vertical line above)

[StefanPeev]

Note: Common Serif font family must be checked for problems with some combining diacritics (macron, breve, vertical line above) in Libertinus Serif #548.

[dwhieb]

I'm not sure if this is quite the same issue, but I ran into a problem with a combined macron + breve:

ū̆ncia