Metacity doesn't have any effects like window fading, so I'm not too
sure. When I switched to Metacity, everything worked fine. It was only
with Compiz I got the ridicously slow loading times.
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Gnome menu is slow when clicking for the first time
https://bugs.launchpad.net/bugs/12040
You receive
I was able to solve the problem by changing the fade mode setting on the
Fading Windows plugin so it uses the Speed setting instead of the Time
setting. I have no clue why it does this, but it solved the problem for
me.
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Gnome menu is slow when clicking for the first time
https://bugs.launchpad