1659207 - When switching between Landscape & Portrait mode in new Print Preview UI, the document preview area and controls are pushed off to the side by the "Preparing Preview" UI

Status: RESOLVED DUPLICATE of bug 1659099

(Toolkit :: Printing, defect)

Description

[Daniel Holbert [:dholbert]]

Attachment: print-screencast.webm

STR:

1. Ideally use a debug build (where things take longer & you're more likely to notice this)
2. Visit https://example.org/
3. Ctrl+P to open the new print/print-preview UI
4. Click "Landscape" or "Portrait" (whichever you're not currently on)

ACTUAL RESULTS:

• The print preview UI (including the old previewed document) suddenly shifts out of the way to the right, to make way for the "Preparing Preview" UI (added in bug 1653323).
• After the new preview is ready, the "Preparing Preview" UI disappears and the actual print-preview UI shifts back into place.

EXPECTED RESULTS:
I think the intent is for the "Preparing Preview" UI to replace the previewed document (while things are updating), not to push it & the controls out of the way.

I'm testing using a mozilla-central debug build from https://hg.mozilla.org/mozilla-central/rev/9bfa6276ddc5

Comment 1

[Daniel Holbert [:dholbert]]

Attachment: screenshot of bug

Comment 2

[Daniel Holbert [:dholbert]]

Emma, perhaps you could take a look here? I suspect this is a case where the new preview from bug 1653323 isn't behaving as expected.

Comment 3

[Daniel Holbert [:dholbert]]

(I haven't tested this in an opt build so I don't know how noticeable this is there, but presumably it's somewhat noticeable, particularly if you're on a slower system or if the portrait->landscape conversion takes a little while for whatever reason.)

Comment 4

[Daniel Holbert [:dholbert]]

update: yeah, this is reproducible in today's Nightly, though for short documents it's fast enough that it just looks like a jarring flicker/jump+jump-back.

But for sufficiently long documents (e.g. gutenberg-hosted Pride & Prejudice[1]), it looks just like my screencast, with a second or so of the side-by-side mis-rendering.

[1] https://www.gutenberg.org/files/1342/1342-h/1342-h.htm