Just recently I found myself needing to edit multiple domains at once (to upgrade PHP and enable pagespeed, as it happens).
I went to the panel, and opened the
domain.manage UI for each domain, opening each domain in a new tab behind the current one.
Then I went through the new tabs one at a time, applying my settings and closing each tab in turn.
To my surprise, I discovered that each time I saved changes in a tab, they would be applied only to the domain associated with the tab that I opened most recently!
This is particularly bad because it led to changes in the directory containing my files for many of my domains, with the result that they received inadvertent "brain transplants" -- some of the domains were serving content from others.
Could this be caused by use of session state to record which domain is being edited? The symptoms are suspiciously similar to those reported in the paper http://www.ccs.neu.edu/racket/pubs/esop2003-gfkf.pdf, where the problems were ultimately caused by unwise use of session state. I notice use of a hidden field in the panel source code that seems like it should identify the domain being edited, but perhaps it is not being used consistently.