Crash when enumerating printers with remote CUPS server.
We got a report of Firefox crashing when trying to print with a remote CUPS server.
The first print job seems to work fine, the second one crashes when enumerating printers deep in GTK internals, see stack here:
https://crash-stats.mozilla.org/report/index/782429e7-d7d4-43d7-91d7-65a520220118
Seems like a null deref / passing a null name to gtk_printer_get_name
from find_printer
.