ui.js tries to highlight whatever's in the URL fragment:

highlightPost( $( '.flow-post' + window.location.hash ) );

without any validation that the selector $( '.flow-postXXX' ) exists, so if the fragment isn't loaded yet, or is just random #stuff, the JavaScript code $elem.offset().top fails. Thereafter page JavaScript like collapse/expand icons don't work.

With ?debug=1, the console shows (Firefox):

[00:07:02.739] TypeError: $elem.offset(...) is undefined @ http://ee-flow.wmflabs.org/w/extensions/Flow/modules/discussion/ui.js:324

or (Chromium):

Uncaught TypeError: Cannot read property 'top' of undefined

We'll need smarter fragment parsing sooner or later.

Version: master
Severity: normal
URL: http://ee-flow.wmflabs.org/wiki/Talk:First_release#bad