I identified a problem in the /program/steps/mail/func.inc regexp for
cleaning html code. To summarize, the cleanup code looks for the word
'on' followed by a number of non-equal characters. This should
identify onchange, onclick, etc... the problem is the code fails when
the word 'on' is outside of an html tag and a tag with an equal sign
(eg. html link) follows it in the email. I saw the problem on order
confirmation emails from Amazon.com.

I created a ticket in trac that contains a patch for this regexp to
verify that the word on is contained inside a tag. The patch is a
unified diff, and I also attached a testcase. View the ticket here: http://trac.roundcube.net/trac.cgi/ticket/1484183

As my first post to this list, I must acknowledge what a truly
fantastic product RoundCube is.

Thanks, Brian