352488 - drawWindow causes transform changes in source window

Status: RESOLVED WORKSFORME

(Core :: Graphics, defect)

Description

[Frank Wein [:mcsmurf]]

SeaMonkey Trunk uses drawWindow to preview tabs, some extensions for Firefox also use drawWindow. So far it did not work because of Bug 324803, but sometime in the last few days (I cannot say for sure, since the official SeaMonkey nightlies still use the old GFX toolkit) it suddenly started working.
The problem is when you now preview a tab, the font sizes in the real tab get scaled down to the font size that is used in the tab preview. You need to reload the page twice to fix the fonts. After the first reload the font size is ok again, but all the text overlaps. After the second reload the page looks ok again.

Comment 1

[Frank Wein [:mcsmurf]]

Bugs that changed canvas code more or less recently are: Bug 351296, Bug 351295, Bug 348351, a commit that removed the 0 from a "if (0 && rootFrame)" and Bug 338786. The first three bugs seem to belong together, Bug 338786 is rather unlikely (too far in the past).

Comment 2

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

(In reply to comment #1)
> a commit that removed the 0 from a "if (0 && rootFrame)"

It was this; that was checked in by accident originally.

Comment 3

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

Attachment: simple drawwindow test

I've seen this with generic drawWindow test cases, but now I can't reproduce.  Attached is a simple drawWindow test case.

Comment 4

[Dave Townsend [:mossop]]

I see this somewhat intermittently caused by my firefox extension (Tab Sidebar). On the page I tested it on nothing changed until after a couple of drawWindow calls. Also not all of the text changed, only certain items.

Comment 5

[Dave Townsend [:mossop]]

A further experiment suggests that this only happens when the canvas you're drawing onto has some scaling applied to it. I guess that makes some sense.

Comment 6

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

The patch in bug 324803 fixes this.

Comment 7

[Vladimir Vukicevic [:vlad] [:vladv] (needinfo me, slow to respond)]

The patch in bug 324803 fixes this.

Comment 8

[Peter van der Woude [:Peter6]]

Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9a1) Gecko/20061026 Minefield/3.0a1 ID:2006102609 [cairo]

It isn't fully fixed, it's just less extreme on most sites

repro:

open Firefox and Use the TabSidebar extension
Open Gmail in a tab
open a mail (a bugmail would be fine)
middleclick on a link.

result:
the link jumps around and the content is misformed
(screenshot next)

Comment 9

[Peter van der Woude [:Peter6]]

Attachment: screenshot

filling forms (e.g. in bugzilla) is an utter nightmare too.

Comment 10

[Frank Wein [:mcsmurf]]

This is how it looked for me after the first reload as a workaround, see Comment 0 (two reloads were needed). The reload workaround stopped working though a few days ago.

Comment 11

[Dave Townsend [:mossop]]

Im totally not seeing any problem with this any longer and unless anyone has any objections I think this can be resolved WFM.

Comment 12

[Dave Townsend [:mossop]]

Seems fine to me