In XUL, Orca flat review works normally on static <description>s. But when the description is added to the document by a script, character reading flat review commands (KP-1/2/3) read the whole text from the given character to the end of the text instead of reading just a single character. You can try it on the following attached file. Open it in a standalone chrome window (e.g. using the --chrome Firefox option; this is important!), press the "Add text" button and try to character flat review "Generated text".
Attachment:
test.xul
Description: application/vnd.mozilla.xul
What's the difference between static and dynamically added elements? Is it an Orca bug or a Firefox bug? Regards, Milan Zamazal