Error messages take forever to load.
In firefox (haven't checked anything else) it takes about 5-6 seconds on a local dev machine (server localhost) and more on remote server.
On my stupid firefox, if i'm in another tab, its another 2-3 seconds to switch to the tab containing error.
The reason? The request_and_response partial which is called in
actionpack/lib/action_controller/templates/rescues/layout.rhtml
renders something called "template parameters". with <%= debug(template_assigns) %>.
In my case, its dumping the contents of every query and variable.. which would be fine, useful even, except that there's a few hundred records in memory.
The file that rails sends me is about 100k in size, which explains (1) the long load/render time and (2) the long switch time and (3) firefox randomly crashing.
Personally, I have never used "template parameters" in my debugging, because generally I know what the error is (usually a stupid one) and what I'm doing to make the error. This is probably different for others ;)
Anyway, if you want a quick and dirty fix, delete the last code line from your
actionpack-(version)/lib/action_controller/templates/rescues/_request_and_response.rhtml
<div id="template_dump" style="display:none"><%= debug(template_assigns) %></div>
Maybe this nasty part could be switched on or off somewhere?