User Agent: Mozilla/5.0 (Windows NT 6.1; rv:6.0) Gecko/20100101 Firefox/6.0 Build ID: 20110811165603 Expected results: A lot of users experience fuzzy fonts as hw acceleration is on by default now, others just don't want hw acceleration enabled (what is the selling point?). Firefox has an option to turn hw acceleration off under Advanced > General. Thunderbird should have this option easily available too.

Confirming per bug 667989.

++vote; :-) On my 1-year old laptop, scrolling the email list paints only about 2 times per second! (Integrated Intel graphics. High system CPU times are reported.) I eventually discovered this option, and it's back to normal now (~20Hz)

I'd like to second that. Intel Mobile Series 4 chipset / Win7, the graphics get unusably slow as soon as drivers that permit HW acceleration are installed. Even worse, the whole graphics interface gets slow. Please add this checkbox in configuration.

Performance problems happen on reasonably new GPUs as well. ATI Radeon HD 5450 (with AMD Catalyst 11.11) Windows 7 64-bit The interface is usable but very slow. Setting "gfx.direct2d.disabled" true and "layers.acceleration.disabled" true resolves the problem. Please add the requested checkbox.

(In reply to mozilla from comment #4) > The interface is usable but very slow. Setting "gfx.direct2d.disabled" true > and "layers.acceleration.disabled" true resolves the problem. These preferences now default to true in Thunderbird 9 and later (see bug 689742). > Please add the requested checkbox. I'm not convinced this bug is needed any longer as the defaults have been changed.

If someone is advanced enough to know what the hardware-acceleration settings actually accomplish I'd assume that they'll also find the preference setting(s) even without them being exposed in the UI, thus - with the new default - I'd consider this WFM now for Thunderbird.

With the new defaults, I agree that this is not important any more. Perhaps someone can close this bug.

wfm, see bug 689742

this is closer to wontfix