I’m seeing an unusual ligature issue when viewing a Prince-generated PDF in the PDF viewer in Microsoft's Edge browser. Automatically generated ligature pairs drop the second of the two letters and stretch the first to fill the space of both characters.

The issue is most obvious in Th pairs but I believe that all automatically created ligature pairs exhibit the issue.

When viewing the output in Acrobat Reader, Firefox and Chrome PDF viewers, the ligatures render correctly.

I've attached a couple of screen caps of the issue and the PDF from which they were taken.

We're using the Minion Pro OpenType font family (version 2.112) in its variants.

I've long since reported the issue to Microsoft, but I was wondering if there was a workaround we could implement on the Prince end.

1. 20190212pm-Hansard-n99.pdf‎ 1.2 MB
2. ligature-issue-edge.png‎ 2.5 kB ‎
   A ligature rendering issue in Edge
3. ligature-issue-edge2.png‎ 16.5 kB

That's bizarre and hilarious, we will investigate.

Possible workarounds would be using a different font or disabling ligatures with this unofficial CSS:

font-variant: prince-opentype(ccmp)

But hopefully Microsoft can fix this issue.