290110 - Text rendering glitch.

Status: RESOLVED WORKSFORME

(Core Graveyard :: GFX: Gtk, defect)

Description

[Javier Kohen]

User-Agent:       Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.6) Gecko/20050324 Epiphany/1.4.8 (Debian package 1.4.8-2)
Build Identifier: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.7.6) Gecko/20050324 Epiphany/1.4.8 (Debian package 1.4.8-2)

Sometimes a whole line is missing from rendered text. Not a text line, but a
one-pixel tall line. I've seen this in Epiphany and Thunderbird; maybe Firefox
1.x, but I don't remember. Epiphany is compiled against Mozilla 1.7.6, but I've
seen this with older versions, too.

I'm using a 64-bit Debian on AMD64. I haven't seen this problem with any other
Gtk+2 app, including Evolution and Eclipse (they also show lots of text). I
might have seen it on a 32-bit Debian as well, but I'm also not sure.

I would have reported this earlier, but it's actually tricky because when you
switch apps Mozilla refreshes the screen, which causes the glitch to go away. I
finally set up a second X Screen and captured Mozilla's screen from there. See
the screenshots below.

Reproducible: Sometimes

Steps to Reproduce:
I'm not aware of a way to reproduce this. It just happens every now and then.

Comment 1

[Javier Kohen]

Attachment: Text with glitch

See the second and third lines. The glitch is more obvious on the latter.

Not that it affects every other line. Usually it's just one line per page, if
at all.

Comment 2

[Javier Kohen]

Attachment: Partially better

In this screen shot the third line has been refreshed by selecting part of the
text with the mouse. Noticeably, the second line still exhibits the glitch.

Comment 3

[Kyle Hokanson]

using the 32 bit build on amd64 with gentoo, I can reproduce this by going to a
page with mostly text of around 11-12pt size, and quickly scrolling by any
method (mouse wheel, scrollbar, etc). I have the smoothwheel extension
installed, and turning it off had no effect.

this seems to happen most often if the text's font is set as any of the
sans-serif fonts.

I have also had this happen when moving a window across a window with text in
it. The missing lines are then vertical.

build: Mozilla/5.0 (X11; U; Linux i686 (x86_64); en-US; rv:1.7.10) Gecko/20050716 

Comment 4

[Kyle Hokanson]

Attachment: Shows the bug when a window is moved over a window with text in it

Comment 5

[Mats Palmgren (inactive)]

Does this bug still occur in a recent trunk build?
http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-trunk/

Comment 6

[Mats Palmgren (inactive)]

-> WORKSFORME