(Spin off bug from bug 645117 comment 13)

Attila said:

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With Gecko based Yelp related:
When I choose an another topic for example with Orca help page, some time I
unable to move the document with arrow keys after I opening the new topic, Orca
not spokening lines, and helppage reading is not beginning automaticaly. If I
remember right, this is a not Orca specific issue and not need fixing this
problem in Orca.
The grab focus on objects when navigating check box is default unchecked, I
nothing change the default created settings file.
I possible reading this situations with help topics contents when I press a Tab
key and jump h key with the topic document heading level.
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And in the next comment he provided:

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Created an attachment (id=183841) [details]
Debug file with show topic reading related problem

This is the debug.out file with I promise.
I not changed any settings with Yelp related, I only created
application-specific file.
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