Created attachment 259933 [details]
This is issue html
This is a epub file, in which "10" is -webkit-text-combine:horizontal. If change to -epub-writing-mode:horizontal-tb, it will be correct.
In epub file, -webkit-text-combine doesn't work well. Please check my attachment, looks it will move a litter higher than normal.
Created attachment 259934 [details]
This is safari debug.
Created attachment 259935 [details]
This is issue text.
Created attachment 460910 [details]
Created attachment 460911 [details]
With '-webkit-text-combine:horizontal' the "10" is rendered in a narrow font that tries to match the width of the glyphs above and below it.
With '-epub-writing-mode:horizontal-tb', the "10" is rendered as a wider block.
I have attached "desired.png" and "bug.png"