1670065 - Firefox chooses unwritable margins of zero for my printer, on Linux (vs. margins of 10-12 on Windows)

Status: NEW

(Core :: Printing: Setup, defect, P3)

Description

[Daniel Holbert [:dholbert]]

When I print to my printer (model "Brother MFC-J6535DW") from Linux, Firefox behaves as if the unwriteable margins are all 0 (and we store those margins in the unwriteable_margin about:config prefs for this printer).

This produces clipped headers/footers at the edge of the page, because in fact the printer cannot print all the way to the edge of the paper.

If I instead print from Windows (in Firefox Nightly), I instead end up with unwriteable margins of 10/12/12/12 (with 10 being the value for the bottom of the page); and there's no clipped headers/footers. So, this is a platform inconsistency of some sort, and a Linux specific bug. (or maybe CUPS=Linux-&-Mac-specific?)

I'm testing using a fresh profile on Linux. I get the same results (0 stored in the printer's unwriteable margins prefs) from our tab-modal print, as well as from the system dialog if I turn off the pint.tab_modal.enabled pref. So this isn't specific to our new UI. (I cleared the unwriteable_margin prefs between each attempt at printing, BTW).