Created attachment 39616 [details]
awt-assertion.txt

Looks like Tools-Options deferred initialization is causing problems. Does it
happen regularily? Thanks.

Actually, David might be interested too. If not, sorry and don't bother.

BTW core/options deferred initialization is causing also one race condition that
I am trying to solve right now.

I have seen even shorter stack traces starting from these:

        at
org.netbeans.modules.options.keymap.KeymapPanelController.getLookup(KeymapPanelController.java:63)
        at
org.netbeans.modules.options.CategoryModel$Category.getLookup(CategoryModel.java:394)
        at
org.netbeans.modules.options.CategoryModel$Category.access$000(CategoryModel.java:283)
        at org.netbeans.modules.options.CategoryModel$1.run(CategoryModel.java:68)

that end up in the assertion error. I thought that the assertion itself is a bit
overkill since even some code that does not violates the swing threading rule
ends up with the same assertion error. My case was not going through windows
manager but I don't know what is wrong on asking an action for a display name
from non AWT thread. That is most probably off-topic for this report but to stay
on topic: if you happen to change something under
org.netbeans.modules.options.keymap please note that I am currently working on a
branch shortcuts_77386 and whatever you change I must propagate there. I suggest
that you either fix it on the branch or leave it to me ;-) Or wait cca 1 week
after I merge the branch ...

I know, I'll wait for you to integrate your changes and then reevaluate this
defect. 

Please reevaluate. Thanks

Haven't seen this one for a long time. So, probably fixed. I'm sure somebody will reopen it should it happen again.