On Mac OS, normal behavior is for the {Up|Down} arrow key to move to the {beginning|end} of a text field -- since you're likely to be subconsciously considering using the {Left|Right} key repeatedly to do this, with your fingers already over that key, moving from there to {Up|Down} is quicker than moving to {Home|End}. However, in Chatzilla, Up and Down scroll through the history list. You suggested a pref for whether (a) Up and Down scroll through the History list (b) Up and Down go to the beginning/end of the input line, and Option+Up and Option+Down scroll through the history list and that the value for the pref should be set based on the platform in the user agent string. I think this is a very good idea.

This bug is targeted at a Mac classic platform/OS, which is no longer supported by mozilla.org. Please re-target it to another platform/OS if this bug applies there as well or resolve this bug. I will resolve this bug as WONTFIX in four weeks if no action has been taken. To filter this and similar messages out, please filter for "mac_cla_reorg".

Generalizing this bug. I don't think just an OS-based pref is enough, given the bug I'm about to dupe to this one...

*** Bug 109235 has been marked as a duplicate of this bug. ***

What do other Mac IRC and IM clients do? I'd rather just match them (and not add a pref) if it's a major inconsistency with other Mac clients.