A comment I posted on

http://mathoverflow.net/questions/98410/does-every-operator-from-a-hilbert-space-to-l0-factor-through-a-canonical-one

went wild. I cannot delete it because the delete button does not show. Will a moderator please delete the comment?

TIA

The trick I use when comments break on math.SE is this: I go into Developer Tools in Chrome (I'm sure other browsers have something equivalent) and delete parts of the page until the delete button for the comment (and, as we have on SE 2.0 sites, the edit button) become accessible. Usually it suffices to delete the div element named "sidebar". One is only deleting these parts of the page on the copy of it currently displaying in the browser, so it doesn't harm the site, but the buttons retain their functionality, so pressing the delete button on a comment will cause it to disappear for good (even after the page is reloaded).

I don't really know very much about web pages, but at least as far I know this method isn't harmful to the site. I'm sure there's a better / more direct way of doing it, but it works consistently. François, is that how you did it?

at least as far I know this method isn't harmful to the site

As you say, this only affects the rendering of the page in your browser so there is no effect whatsoever on the site. I frequently use this technique on sites with bad design (though I use Firebug in Firefox).