w3m-end-of-line, kill-line should stop at whitespace

[jidanni@xxxxxxxxxxx]

On the Location: line at the top of a page do C-e (w3m-end-of-line),
it should stop at the last character. Not the end of the screen.
Do C-k and then paste later with C-y, you'll see all these blanks appended:
"Location: http://en.wikipedia.org/wiki/Who_Let_the_Dogs_Out%3F             "
                                                               ^^^^^^^^^^^^^
I notice the same problem with any text in HTML <div align="center"> too.
emacs-w3m-version "1.4.263"