1668453 - Scroll print preview on PgUp/PgDown/Home/End when they would otherwise do nothing

Status: NEW

(Toolkit :: Printing, enhancement, P3)

Description

[Daniel Holbert [:dholbert]]

STR:

1. Ensure you have print.tab_modal.enabled = true
2. Visit some long page like https://www.mozilla.org/en-US/MPL/2.0/
3. Open the print dialog (e.g. Ctrl+P)
4. Press your PageDown key (on your keyboard), and then your PageUp key. (Try "home" & "end" keys as well)

EXPECTED RESULTS:
I would expect that I'd page through the preview.

ACTUAL RESULTS:
These keypresses seem to actually cycle me through the options in my print "Destination" dropdown-menu.

If I click the document, then I get expected results. But until I do that, these keypresses cycle through the Destination menu.

For comparison: in Chrome, I get EXPECTED RESULTS from these STR, for PageUp and PageDown. (The Home/End keys simply have no effect there, for some reason, until I've clicked the document to explicitly focus it.)

Comment 1

[Daniel Holbert [:dholbert]]

(I'm encountering this bug using yesterday's Nightly btw -- Nightly 83.0a1 (2020-09-30) (64-bit) on Linux. I assume earlier versions are also affected, though I haven't checked.)

Comment 2

[Mark Striemer [:mstriemer]]

This is what I would expect to happen (well sort of, I didn't realise those keys did anything in a select till now). Chrome seems to have some handlers where some elements will proxy these keys to scroll the preview document (interestingly not the Home/End ones though).

We focus the print destination select on load, I don't really think we should override the default behaviour for a select to trigger the next/prev page for the PgDn/PgUp buttons. If you open the more settings section on Chrome then the settings pane becomes scrollable and the behaviour changes slightly, but they still scroll the preview when the Print or Cancel button is focused since they're outside of the scrollable settings panel.

We could definitely do something for when there is no focused element in the settings panel or if the focused element doesn't do anything for PgUp/PgDn/Home/End (I guess just not a select?).

Putting this in 83 but I suspect it'll slip.

Comment 3

[Blake Winton (:bwinton) (:☕️)]

(Moving bugs to 86, part 1.)

Comment 4

[Blake Winton (:bwinton) (:☕️)]

Moving things to 88, cause we're mostly on Proton these days…