976661 - JS console goes blank when scrolling to the right

Status: RESOLVED WORKSFORME

(DevTools :: Console, defect)

Description

[mwc]

Attachment: recorded.gif

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:30.0) Gecko/20100101 Firefox/30.0 (Beta/Release)
Build ID: 20140218030202

Steps to reproduce:

I opened Firefox Nightly (version: 30.0a1 (2014-02-18)).  Fedora 20 with up-to-date packages.  I'll happily provide any logs or package versions or anything needed!  After a couple of years of mostly-Chrome, I am *loving* the way Firefox is headed and my fellow Red Hat devs are impressed too.  Anyway, on to the issue:

Navigate to about:blank.  Press F12 to open the devtools (mine are docked to the right).

Paste a long line of code into the console.  I used this:

    console.log({}) // -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Click on the `[object Object]` to  bring up the Object inspector pane.

Grab the horizontal scrollbar with your mouse cursor and drag it to the right.


Actual results:

See attached gif recording of the bug.  The console screen goes partially blank (black) when scrolling to the right and returns when scrolling back to the left.

It can be very hard to reproduce.

Keep grabbing the scrollbar, scrolling to the right, scrolling back to the left, releasing.  Keep trying that and eventually it will happen.  It has taken me as many as 20 tries before the console starts blanking out.  Sometimes I can't get it to happen at all.  I wish I had time to come up with a 100% reproducer but this is all I've got for now.


Expected results:

Console's text scrolls to the right without blanking out.

Comment 1

[Manuela Muntean [Away]]

Couldn't reproduce it with latest Nightly on Ubuntu 13.10 32-bit.

Could you please try the following :

1) try this with a clean profile: http://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

2) running in Safe mode: http://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

Comment 2

[[:Aleksej]]

Couldn't reproduce with 2014-03-02-03-02-03-mozilla-central-firefox-30.0a1.ru.linux-x86_64 without hardware acceleration.