Bug#946896: hyphenation change in 1.44 series causes rendering differences

[Iain Lane]

Package: libpango-1.0-0
Version: 1.44.7-1
Severity: normal
Tags: upstream

Control: forwarded -1 https://gitlab.gnome.org/GNOME/pango/issues/438

Please read the linked bug for full details.

Upstream commit eb4882cada397268948ec24da046ff75615dfb9e made some
changes relating to hyphenation - the part of pango's layouting
algorithm that decides when it should insert a hyphen when breaking
lines in the middle of paragraphs (because there isn't enough vertical
space). Somehow this results in extra whitespace being inserted when it
wasn't before. I think this is a regression (i.e. not an intended
rendering change).

The only practical impact that I know of so far is that it breaks
gtk+3.0's reftests. In Ubuntu we had already updated to the 1.44 series
before we discovered this impact - as a consequence we have marked the
particular reftests as "known fail":

  https://git.launchpad.net/~ubuntu-desktop/ubuntu/+source/gtk+3.0/commit/?id=315462e7c8cfabc755e6bcb420963e80bba6b22f

Cheers,

-- 
Iain Lane                                  [ iain at orangesquash.org.uk ]
Debian Developer                                   [ laney at debian.org ]
Ubuntu Developer                                   [ laney at ubuntu.com ]