We could check whether a specific search term is present on the current page on
page load and disable the jump-to-word buttons accordingly instead of needing
the user to click on a button once.
This would cause some overhead on initial page load though (how much?), so
potentially this should be opt-in and controlled through a preference.
( Originally reported as a review on AMO, see
https://addons.mozilla.org/firefox/addon/searchwp/reviews/632074/ )