Bugzilla

Here's a [pernosco trace](https://pernos.co/debug/gtw6qGwINUg5h7EqxoiQAg/index.html#f{m[BT+F,AQ_,t[KQ,CxkM_,f{e[BT+C,8C6/_,s{adf1eYAAA,bEDk,uFjgRWg,oFj6MAA___,v[{wiLg,v[{f'list',q'stdouterr',p{_,xAYag_,{f'container',q'stack',p{_,xAYag_,{f'list',q'explainer',p{'explainFocus'{'data'{'producer'{'subrange'{'producer'{'memory'{'addressSpace'{'execs'Aw,'task'{'serial'KQ,'tid'CxkM__,'ranges'[{'end'f/zrVUnQ,'start'f/zrVUmT____,'subrange'{'start'NQ,'end'Ng___,'renderer''utf8'_,'frame'.,'moment'{'event'BT+F,'instr'AQ_,'node'AQ,'tuid'{'serial'KQ,'tid'CxkM__,'focusSelector''output'_,xAYag___,{w/eg,v[{f'source',q'source',p{_,xAYag_,{f'list',q'file-search',p{'file''Stdouterr','regex''6x7','type_''Write'_,xAYag____/) of me printing example.org to my aforementioned PDF printer with 6x7 paper size (and ending up with 6x7 page on an A4-sized PDF).

I've poked around in pernosco and added some guideposts in the Notebook view, but I'm not yet sure where things go wrong.

It does look like our custom size name (`custom_6x7in_6x7in_borderless`) comes from CUPS, and GTK complains when given that custom size name, but it's still happy to store it as a size-name.  And we do seem to set the correct actual dimensions (in nsPrintSettingsGTK::mPrintSettings) when we set it up, in the `nsPrintSettingsGTK` instantiations I've traced through.

Here's a [pernosco trace](https://pernos.co/debug/gtw6qGwINUg5h7EqxoiQAg/index.html#f{m[BT+F,AQ_,t[KQ,CxkM_,f{e[BT+C,8C6/_,s{adf1eYAAA,bEDk,uFjgRWg,oFj6MAA___,v[{wiLg,v[{f'list',q'stdouterr',p{_,xAYag_,{f'container',q'stack',p{_,xAYag_,{f'list',q'explainer',p{'explainFocus'{'data'{'producer'{'subrange'{'producer'{'memory'{'addressSpace'{'execs'Aw,'task'{'serial'KQ,'tid'CxkM__,'ranges'[{'end'f/zrVUnQ,'start'f/zrVUmT____,'subrange'{'start'NQ,'end'Ng___,'renderer''utf8'_,'frame'.,'moment'{'event'BT+F,'instr'AQ_,'node'AQ,'tuid'{'serial'KQ,'tid'CxkM__,'focusSelector''output'_,xAYag___,{w/eg,v[{f'source',q'source',p{_,xAYag_,{f'list',q'file-search',p{'file''Stdouterr','regex''6x7','type_''Write'_,xAYag____/) of me printing example.org to my aforementioned PDF printer with 6x7 paper size (and ending up with 6x7 page on an A4-sized PDF).

I've poked around in pernosco and added some guideposts in the Notebook view, but I'm not yet sure where things go wrong.

It does look like our custom size name (`custom_6x7in_6x7in_borderless`) comes from CUPS, and GTK complains when given that custom size name, but it's still happy to store it as a size-name.  And we do seem to set the correct actual dimensions (in `nsPrintSettingsGTK::mPrintSettings`) when we set it up, in the `nsPrintSettingsGTK` instantiations I've traced through.