Thunderbird - page down button.....???

I would like to add a button in thunderbird that does a page down
in a group of headers.....

Checked google but could not find anything like that....

Found an add-on button that moves one message at a time...but
want a page down....or alternately a move to end of messages...

Thank you for any help.....sno

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Correct Scientific Terminology:
Hypothesis - a guess as to why or how something occurs
Theory - a hypothesis that has been checked by enough experiments
to be generally assumed to be true.
Law - a hypothesis that has been checked by enough experiments
in enough different ways that it is assumed to be truer then a theory.
Note: nothing is proven in science, things are assumed to be true.

sno