Enabling Azure for content slows down tab animations. The weird thing is that FX_TAB_ANIM_CLOSE_MS and FX_TAB_ANIM_OPEN_MS are similar (~300ms with or without the option set). But the animation with the option set to true is noticeably slower (mainly the opacity transition).

I figured out this problem occurs only if browser.newtab.preload=true.

With browser.newtab.preload=true, FX_TAB_ANIM_CLOSE_MS is ~30ms longer with gfx.content.azure.enabled=true than with gfx.content.azure.enabled=false.

Isn't the difference between gfx.content.azure.enabled=true and gfx.content.azure.enabled=false worth investigating?

(In reply to Marco Castelluccio [:marco] from comment #4) > Isn't the difference between gfx.content.azure.enabled=true and > gfx.content.azure.enabled=false worth investigating? Yeah, sorry, I think it might be worth investigating why excessive invalidation is more expensive with Azure enabled.

I think this -might- be related to bug 778367. I'm currently debugging an issue with that bug, we can try again after that.

We should retest on tomorrow's nightly which will have the fix to bug 778367

(In reply to Bas Schouten (:bas.schouten) from comment #7) > We should retest on tomorrow's nightly which will have the fix to bug 778367 Marco, can you retest?

Can you still reproduce the issue with latest version with clean new fresh profile without any addons and plugins?

The configuration option doesn't seem to exist anymore, so I wouldn't know how to test this.

FYI - Auzre is probably forced enabled now. So if this issue is not present anymore it's good.