Bug#1082676: librsvg2-common: name of pixbuf loader changed, causes temporary loss of svg support

[Chris Hofstaedtler]

Package: librsvg2-common
Version: 2.59.0+dfsg-3
Severity: normal
Control: affects -1 src:wofi

Hi!

While upgrading a bunch of packages, including librsvg2-common from
2.58.0+dfsg-1 to 2.59.0+dfsg-3, I've noticed various programs
failing. As an example, wofi - the program I use to spawn a new
terminal - aborts like this:

(wofi:12213): Gtk-WARNING **: 19:25:21.851: Could not load a pixbuf
from icon theme.
This may indicate that pixbuf loaders or the mime database could not
be found.

Gtk:ERROR:../../../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon:
assertion failed (error == NULL): Failed to load
/usr/share/icons/Papirus-Dark/16x16/actions/image-missing.svg:
Unable to load image-loading module:
/usr/lib/aarch64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-svg.so:
/usr/lib/aarch64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-svg.so:
cannot open shared object file: No such file or directory
(gdk-pixbuf-error-quark, 5)
Bail out!
Gtk:ERROR:../../../gtk/gtkiconhelper.c:495:ensure_surface_for_gicon:
assertion failed (error == NULL): Failed to load
/usr/share/icons/Papirus-Dark/16x16/actions/image-missing.svg:
Unable to load image-loading module:
/usr/lib/aarch64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-svg.so:
/usr/lib/aarch64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-svg.so:
cannot open shared object file: No such file or directory
(gdk-pixbuf-error-quark, 5)
[1]    12213 abort (core dumped)  wofi --show drun -p Search -n -i
-I -W 66% -s $HOME/.config/wofi.css

Indeed, libpixbufloader-svg.so does not exist in 
/usr/lib/aarch64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/.
However, in the same directory "libpixbufloader_svg.so" exists. Note
the underscore vs. the expected dash in the filename.

Note that I'm upgrading a medium-speed aarch64 system. After the
upgrade finished, everything works again. I assume postinst scripts
needed to run.

Given all the other loaders in gdk-pixbuf-2.0/2.10.0/loaders/ follow
the "libpixbufloader-<format>.so" convention, AND the svg loader did
too in the past (in bookworm and previously in sid), maybe this is
an oversight and should be corrected?  That would avoid temporarily
breaking svg support during upgrades.

Thanks for considering,
Chris