Honestly flummoxed. This works when I fire it on the random div to log 'fun' to the console, but, if I change it to .select-checkbox or td I get no response.
The td cell in question does include a :before and an :after to render a checkbox-like-checkbox, so maybe there's some weird interference there...
$('td.select-checkbox').mousedown(function(){
console.log('fun')
});
Alternatively, though I have trouble believing and/or googling this, the JQuery Docs seem to state that mousedown only works on divs... like maybe actual div
Perhaps the table cells are dynamically loaded and therefore the handler is not registered on page load correctly. In which case you can register it on 'body' instead:
mousedown not working on dynamically loaded element