*** Original post on bio 1624 by Vincent Capelle <vicnett AT gmail.com> at 2012-08-09 00:23:00 UTC *** When going back to a conversation with a lot of unread messages, Home and End work as intended to jump directly to where the first unread message is. Alt+PgUp/PgDn should do the same, but in Ubuntu with Unity, it jumps to the very top or very bottom of the conversation. If the conversation was put on hold at any point, then Alt+PgUp/PgDn does work as intended, but if the conversation is not put on hold again but has unread messages again, then instead of also jumping to the first unread message, it only jumps to where the conversation had previously been put on hold. This is likely due to this Unity bug: https://bugs.launchpad.net/ubuntu/+source/unity-2d/+bug/947468 The Alt key in Unity is bound to summon the HUD, and it interferes with Alt+<key> shortcuts in various applications. Following the steps outlined at http://askubuntu.com/questions/122209/how-do-i-modify-or-disable-the-huds-use-of-the-alt-key to disable the HUD shortcut solves the issue as a workaround.
*** Original post on bio 1624 at 2012-08-09 09:24:04 UTC *** The reason this happens is that pressing the Alt key switches focus, if briefly, to the HUD. This causes the unread ruler to disappear (as IB thinks it's the user switching to another window) and so by the time IB receives the keypress, it can't be jumped to. Another workaround is to use Home/End rather than Alt-PgUp/PgDn (does the same thing). It's possible as per https://bugs.launchpad.net/unity/+bug/934610 that Canonical considers their current Alt key behaviour fixed already (since Unity 5.6). Maybe I should file a bug on Launchpad...
*** Original post on bio 1624 at 2012-08-09 09:45:13 UTC *** Filed as https://bugs.launchpad.net/unity/+bug/1034811
*** Original post on bio 1624 at 2012-08-10 09:38:47 UTC *** Now https://bugs.launchpad.net/ubuntu/+source/unity/+bug/971462