I am typing these characters:
<tr>
What I get instead is
<tr:attribute></tr:attribute>
This is because I use Trinidad:
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:tr="http://myfaces.apache.org/trinidad"
...
and "attribute" is the first tag in that library.
That (and a couple of other issues with xml editing) is currently driving me nuts.
A possible solution for this quirk could be to also add the html tags to the completion list.