easy search function for IRC chat window

Thank you for your bug report, there is a similar request on https://bugzilla.gnome.org/show_bug.cgi?id=585168

That's fixed upstream now.

how to reproduce this?

This bug was fixed in the package empathy - 2.29.6-0ubuntu1

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empathy (2.29.6-0ubuntu1) lucid; urgency=low

  [ Ken VanDine ]
  * debian/patches/20_libindicate.patch:
    - split out notification related stuff into separate patches
  * debian/patches/35_check_actions_notifications.patch
    - If notifications support actions, inhibit updates
  * debian/patches/32_append_notifications.patch
    - use built in empathy functions to check caps

  [ Steve Langasek ]
  * debian/control: have empathy-common Breaks: libempathy-{gtk-,}common
    and empathy-doc instead of conflicting with them, and drop the Provides:;
    the special semantics of C/R/P aren't applicable here, and in fact seem
    to confuse update-manager in some cases into refusing to upgrade empathy.

  [ Didier Roche ]
  * New upstream release
    - #603472, Rename "Hidden" to "Invisible" (G.Balaji) (LP: #489097)
    - #606329, Buttons in GtkInfoBar are too big. (Felix Kaser)
    - #573407, Empathy and telepathy-idle don't pass on server commands to
               server (LP: #509802, #397504)
    - #585168, Scrollback search and jump-to-highlight would be nice.
               (Thomas Meire) (LP: #447097)
    - #596575, Automatic salut account creation doesn't work
              (Guillaume Desmottes) (LP: #437396)
    - #599159, Stop to handle tube channels (Guillaume Desmottes)
    - #599163, Should use ContactCapability to get A/V caps
               (Guillaume Desmottes)
    - #599164, Should use ContactCapability to get FT caps (Guillaume Desmottes)
    - #600693, Empathy calls xmlCleanupParser() where it shouldn't
               (Guillaume Desmottes)
    - #600949, Deleting accounts from the treeview is weird
    - #603498, Escaped text displayed in notifications (Guillaume Desmottes)
    - #606642, IRC account: "Connect" button is not sensitive when changing the
               IRC network (Guillaume Desmottes)
    - #606753, Scrollback search is not case sensitive
    - #607207, show protocol icons in compact view (Guillaume Desmottes)
    - #607306, /join fails to work on the latest version of empathy
               (Thomas Meire) (LP: #509160)
    - #607436, Salut account should only automatically created when the wizard
               is run (Guillaume Desmottes)
    - #607455, Misc fixes regarding the accounts assistant (Guillaume Desmottes)
    - #607463, Edit Custom Messages window is too narrow (Ken VanDine)
               (LP: #502996)
    - #607868, Change Hidden to Invisible in docs
    - #607925, edit account from infobar does not open the right account
               (Guillaume Desmottes)
    - #608043, Should ellipsize text in connection error infobars
               (Will Thompson)
    - #604700, (null) status infobar with IRC account (Guillaume Desmottes)
    - #604706, infobar shows no icon if the presence is empty (Felix Kaser)
    - #605309, Show the status of accounts in the treeview (Guillaume Desmottes)
               (LP: #470096)
    - #605532, on account-creation some field should be persistent over a
               protocol change (Guillaume Desmottes)
    - #606510, Unclear string meaning (Guillaume Desmottes)
    - #585364, Get rid of...