Firefox testing - offscreen surfaces and OMTC

[drago01]

On Mon, Aug 24, 2015 at 10:18 AM, Martin Stransky <stransky at redhat.com> wrote:
> On 08/24/2015 09:43 AM, drago01 wrote:
>>
>> On Mon, Aug 24, 2015 at 8:54 AM, Martin Stransky <stransky at redhat.com>
>> wrote:
>>>
>>> On 08/21/2015 08:28 PM, Thomas Daede wrote:
>>>>
>>>>
>>>> I've been running nightly with this enabled for quite a while on Intel
>>>> and it's been fine.
>>>>
>>>> Note that OMTC is required for e10s.
>>>
>>>
>>>
>>> If you mean OMTC by "this" then you're right - it works fine on nightly
>>> because nightly is built with in-tree cairo. Fedora it built with system
>>> cairo which causes crashes with OMTC enabled. First build which supports
>>> in-tree cairo & Gtk3 is FF41.
>>
>>
>> Why? What's the difference between the in-tree and the system cairo?
>> Ist it newer? Older? Patched? Or just built with a different
>> configuration?
>
>
> in-tree cairo is a cairo library intergated in firefox tree, patched for
> mozilla needs and used for internal rendering. system cairo is a cairo
> library shipped in Fedora and used by gtk3 to draw.

I know what system and in-tree means .. the question was whether
mozilla patched the in-tree version or if it is just a different
version than the system cairo.
Your comment implies the former.