I have the following code
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Having just struggled with this - I'll explain my situation.
I have my tabs within a bootstrap modal and set the following on load (pre the modal being triggered):
$('#subMenu li:first-child a').tab('show');
Whilst the tab was selected the actual pane wasn't visible. As such you need to add active class to the pane as well:
$('#profile').addClass('active');
In my case the pane had #profile (but this could have easily been .pane:first-child) which then displayed the correct pane.