17 files changed, 329 insertions, 19 deletions
diff --git a/indra/newview/CMakeLists.txt b/indra/newview/CMakeLists.txt
index fff1597fd9..98151e2f4d 100644
--- a/indra/newview/CMakeLists.txt
+++ b/indra/newview/CMakeLists.txt
@@ -201,6 +201,7 @@ set(viewer_SOURCE_FILES
     llfloatercamera.cpp
     llfloatercamerapresets.cpp
     llfloaterchangeitemthumbnail.cpp
+    llfloaterchatmentionpicker.cpp
     llfloaterchatvoicevolume.cpp
     llfloaterclassified.cpp
     llfloatercolorpicker.cpp
@@ -870,6 +871,7 @@ set(viewer_HEADER_FILES
     llfloaterbuyland.h
     llfloatercamerapresets.h
     llfloaterchangeitemthumbnail.h
+    llfloaterchatmentionpicker.h
     llfloatercamera.h
     llfloaterchatvoicevolume.h
     llfloaterclassified.h
diff --git a/indra/newview/llappviewer.cpp b/indra/newview/llappviewer.cpp
index edc70030b4..7e7aa521d3 100644
--- a/indra/newview/llappviewer.cpp
+++ b/indra/newview/llappviewer.cpp
@@ -475,7 +475,7 @@ static void deferred_ui_audio_callback(const LLUUID& uuid)
 
 bool    create_text_segment_icon_from_url_match(LLUrlMatch* match,LLTextBase* base)
 {
-    if(!match || !base || base->getPlainText())
+    if (!match || match->getSkipProfileIcon() || !base || base->getPlainText())
         return false;
 
     LLUUID match_id = match->getID();
diff --git a/indra/newview/llavatarlist.cpp b/indra/newview/llavatarlist.cpp
index 8f858fe4e1..f206474e71 100644
--- a/indra/newview/llavatarlist.cpp
+++ b/indra/newview/llavatarlist.cpp
@@ -141,6 +141,7 @@ LLAvatarList::LLAvatarList(const Params& p)
 , mShowSpeakingIndicator(p.show_speaking_indicator)
 , mShowPermissions(p.show_permissions_granted)
 , mShowCompleteName(false)
+, mForceCompleteName(false)
 {
     setCommitOnSelectionChange(true);
 
@@ -177,7 +178,7 @@ void LLAvatarList::setShowIcons(std::string param_name)
 
 std::string LLAvatarList::getAvatarName(LLAvatarName av_name)
 {
-    return mShowCompleteName? av_name.getCompleteName(false) : av_name.getDisplayName();
+    return mShowCompleteName? av_name.getCompleteName(false, mForceCompleteName) : av_name.getDisplayName();
 }
 
 // virtual
@@ -364,7 +365,7 @@ void LLAvatarList::updateAvatarNames()
     for( std::vector<LLPanel*>::const_iterator it = items.begin(); it != items.end(); it++)
     {
         LLAvatarListItem* item = static_cast<LLAvatarListItem*>(*it);
-        item->setShowCompleteName(mShowCompleteName);
+        item->setShowCompleteName(mShowCompleteName, mForceCompleteName);
         item->updateAvatarName();
     }
     mNeedUpdateNames = false;
@@ -404,6 +405,11 @@ boost::signals2::connection LLAvatarList::setItemDoubleClickCallback(const mouse
     return mItemDoubleClickSignal.connect(cb);
 }
 
+boost::signals2::connection LLAvatarList::setItemClickedCallback(const mouse_signal_t::slot_type& cb)
+{
+    return mItemClickedSignal.connect(cb);
+}
+
 //virtual
 S32 LLAvatarList::notifyParent(const LLSD& info)
 {
@@ -418,7 +424,7 @@ S32 LLAvatarList::notifyParent(const LLSD& info)
 void LLAvatarList::addNewItem(const LLUUID& id, const std::string& name, bool is_online, EAddPosition pos)
 {
     LLAvatarListItem* item = new LLAvatarListItem();
-    item->setShowCompleteName(mShowCompleteName);
+    item->setShowCompleteName(mShowCompleteName, mForceCompleteName);
     // This sets the name as a side effect
     item->setAvatarId(id, mSessionID, mIgnoreOnlineStatus);
     item->setOnline(mIgnoreOnlineStatus ? true : is_online);
@@ -432,6 +438,7 @@ void LLAvatarList::addNewItem(const LLUUID& id, const std::string& name, bool is
 
 
     item->setDoubleClickCallback(boost::bind(&LLAvatarList::onItemDoubleClicked, this, _1, _2, _3, _4));
+    item->setMouseDownCallback(boost::bind(&LLAvatarList::onItemClicked, this, _1, _2, _3, _4));
 
     addItem(item, id, pos);
 }
@@ -550,6 +557,11 @@ void LLAvatarList::onItemDoubleClicked(LLUICtrl* ctrl, S32 x, S32 y, MASK mask)
     mItemDoubleClickSignal(ctrl, x, y, mask);
 }
 
+void LLAvatarList::onItemClicked(LLUICtrl* ctrl, S32 x, S32 y, MASK mask)
+{
+    mItemClickedSignal(ctrl, x, y, mask);
+}
+
 bool LLAvatarItemComparator::compare(const LLPanel* item1, const LLPanel* item2) const
 {
     const LLAvatarListItem* avatar_item1 = dynamic_cast<const LLAvatarListItem*>(item1);
diff --git a/indra/newview/llavatarlist.h b/indra/newview/llavatarlist.h
index af5bfefcde..f99da93a3d 100644
--- a/indra/newview/llavatarlist.h
+++ b/indra/newview/llavatarlist.h
@@ -96,11 +96,13 @@ public:
 
     boost::signals2::connection setItemDoubleClickCallback(const mouse_signal_t::slot_type& cb);
 
+    boost::signals2::connection setItemClickedCallback(const mouse_signal_t::slot_type& cb);
+
     virtual S32 notifyParent(const LLSD& info);
 
     void handleDisplayNamesOptionChanged();
 
-    void setShowCompleteName(bool show) { mShowCompleteName = show;};
+    void setShowCompleteName(bool show, bool force = false) { mShowCompleteName = show; mForceCompleteName = force; };
 
 protected:
     void refresh();
@@ -113,6 +115,7 @@ protected:
     void updateLastInteractionTimes();
     void rebuildNames();
     void onItemDoubleClicked(LLUICtrl* ctrl, S32 x, S32 y, MASK mask);
+    void onItemClicked(LLUICtrl* ctrl, S32 x, S32 y, MASK mask);
     void updateAvatarNames();
 
 private:
@@ -127,6 +130,7 @@ private:
     bool mShowSpeakingIndicator;
     bool mShowPermissions;
     bool mShowCompleteName;
+    bool mForceCompleteName;
 
     LLTimer*                mLITUpdateTimer; // last interaction time update timer
     std::string             mIconParamName;
@@ -138,6 +142,7 @@ private:
 
     commit_signal_t mRefreshCompleteSignal;
     mouse_signal_t mItemDoubleClickSignal;
+    mouse_signal_t mItemClickedSignal;
 };
 
 /** Abstract comparator for avatar items */
diff --git a/indra/newview/llavatarlistitem.cpp b/indra/newview/llavatarlistitem.cpp
index 880910d18e..6ef45ed160 100644
--- a/indra/newview/llavatarlistitem.cpp
+++ b/indra/newview/llavatarlistitem.cpp
@@ -78,6 +78,7 @@ LLAvatarListItem::LLAvatarListItem(bool not_from_ui_factory/* = true*/)
     mShowProfileBtn(true),
     mShowPermissions(false),
     mShowCompleteName(false),
+    mForceCompleteName(false),
     mHovered(false),
     mAvatarNameCacheConnection(),
     mGreyOutUsername("")
@@ -324,13 +325,11 @@ void LLAvatarListItem::setShowProfileBtn(bool show)
 
 void LLAvatarListItem::showSpeakingIndicator(bool visible)
 {
-    // Already done? Then do nothing.
-    if (mSpeakingIndicator->getVisible() == (bool)visible)
-        return;
-// Disabled to not contradict with SpeakingIndicatorManager functionality. EXT-3976
-// probably this method should be totally removed.
-//  mSpeakingIndicator->setVisible(visible);
-//  updateChildren();
+    if (mSpeakingIndicator)
+    {
+        mSpeakingIndicator->setIsActiveChannel(visible);
+        mSpeakingIndicator->setShowParticipantsSpeaking(visible);
+    }
 }
 
 void LLAvatarListItem::setAvatarIconVisible(bool visible)
@@ -417,8 +416,8 @@ void LLAvatarListItem::onAvatarNameCache(const LLAvatarName& av_name)
     mAvatarNameCacheConnection.disconnect();
 
     mGreyOutUsername = "";
-    std::string name_string = mShowCompleteName? av_name.getCompleteName(false) : av_name.getDisplayName();
-    if(av_name.getCompleteName() != av_name.getUserName())
+    std::string name_string = mShowCompleteName? av_name.getCompleteName(false, mForceCompleteName) : av_name.getDisplayName();
+    if(av_name.getCompleteName(false, mForceCompleteName) != av_name.getUserName())
     {
         mGreyOutUsername = "[ " + av_name.getUserName(true) + " ]";
         LLStringUtil::toLower(mGreyOutUsername);
diff --git a/indra/newview/llavatarlistitem.h b/indra/newview/llavatarlistitem.h
index 2e4c597d30..2ec7a41055 100644
--- a/indra/newview/llavatarlistitem.h
+++ b/indra/newview/llavatarlistitem.h
@@ -106,7 +106,7 @@ public:
     void setShowPermissions(bool show) { mShowPermissions = show; };
     void showLastInteractionTime(bool show);
     void setAvatarIconVisible(bool visible);
-    void setShowCompleteName(bool show) { mShowCompleteName = show;};
+    void setShowCompleteName(bool show, bool force = false) { mShowCompleteName = show; mForceCompleteName = force;};
 
     const LLUUID& getAvatarId() const;
     std::string getAvatarName() const;
@@ -220,6 +220,7 @@ private:
     bool mHovered;
 
     bool mShowCompleteName;
+    bool mForceCompleteName;
     std::string mGreyOutUsername;
 
     void fetchAvatarName();
diff --git a/indra/newview/llfloaterchatmentionpicker.cpp b/indra/newview/llfloaterchatmentionpicker.cpp
new file mode 100644
index 0000000000..1cfed122a9
--- /dev/null
+++ b/indra/newview/llfloaterchatmentionpicker.cpp
@@ -0,0 +1,184 @@
+/**
+ * @file llfloaterchatmentionpicker.cpp
+ *
+ * $LicenseInfo:firstyear=2025&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2025, Linden Research, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#include "llviewerprecompiledheaders.h"
+
+#include "llfloaterchatmentionpicker.h"
+
+#include "llavatarlist.h"
+#include "llfloaterimcontainer.h"
+#include "llchatmentionhelper.h"
+#include "llparticipantlist.h"
+
+LLUUID LLFloaterChatMentionPicker::sSessionID(LLUUID::null);
+
+LLFloaterChatMentionPicker::LLFloaterChatMentionPicker(const LLSD& key)
+: LLFloater(key), mAvatarList(NULL)
+{
+    // This floater should hover on top of our dependent (with the dependent having the focus)
+    setFocusStealsFrontmost(false);
+    setBackgroundVisible(false);
+    setAutoFocus(false);
+}
+
+bool LLFloaterChatMentionPicker::postBuild()
+{
+    mAvatarList = getChild<LLAvatarList>("avatar_list");
+    mAvatarList->setShowCompleteName(true, true);
+    mAvatarList->setFocusOnItemClicked(false);
+    mAvatarList->setItemClickedCallback([this](LLUICtrl* ctrl, S32 x, S32 y, MASK mask)
+    {
+        if (LLAvatarListItem* item = dynamic_cast<LLAvatarListItem*>(ctrl))
+        {
+            selectResident(item->getAvatarId());
+        }
+    });
+    mAvatarList->setRefreshCompleteCallback([this](LLUICtrl* ctrl, const LLSD& param)
+    {
+        if (mAvatarList->numSelected() == 0)
+        {
+            mAvatarList->selectFirstItem();
+        }
+    });
+
+    return LLFloater::postBuild();
+}
+
+void LLFloaterChatMentionPicker::onOpen(const LLSD& key)
+{
+    buildAvatarList();
+    mAvatarList->setNameFilter(key.has("av_name") ? key["av_name"].asString() : "");
+
+    gFloaterView->adjustToFitScreen(this, false);
+}
+
+uuid_vec_t LLFloaterChatMentionPicker::getParticipantIds()
+{
+    LLParticipantList* item = dynamic_cast<LLParticipantList*>(LLFloaterIMContainer::getInstance()->getSessionModel(sSessionID));
+    if (!item)
+    {
+        LL_WARNS() << "Participant list is missing" << LL_ENDL;
+        return {};
+    }
+
+    uuid_vec_t avatar_ids;
+    LLFolderViewModelItemCommon::child_list_t::const_iterator current_participant_model = item->getChildrenBegin();
+    LLFolderViewModelItemCommon::child_list_t::const_iterator end_participant_model = item->getChildrenEnd();
+    while (current_participant_model != end_participant_model)
+    {
+        LLConversationItem* participant_model = dynamic_cast<LLConversationItem*>(*current_participant_model);
+        if (participant_model)
+        {
+            avatar_ids.push_back(participant_model->getUUID());
+        }
+        current_participant_model++;
+    }
+    return avatar_ids;
+}
+
+void LLFloaterChatMentionPicker::buildAvatarList()
+{
+    uuid_vec_t& avatar_ids = mAvatarList->getIDs();
+    avatar_ids = getParticipantIds();
+    updateAvatarList(avatar_ids);
+    mAvatarList->setDirty();
+}
+
+void LLFloaterChatMentionPicker::selectResident(const LLUUID& id)
+{
+    if (id.isNull())
+        return;
+
+    setValue(stringize("secondlife:///app/agent/", id.asString(), "/mention "));
+    onCommit();
+    LLChatMentionHelper::instance().hideHelper();
+}
+
+void LLFloaterChatMentionPicker::onClose(bool app_quitting)
+{
+    if (!app_quitting)
+    {
+        LLChatMentionHelper::instance().hideHelper();
+    }
+}
+
+bool LLFloaterChatMentionPicker::handleKey(KEY key, MASK mask, bool called_from_parent)
+{
+    if (mask == MASK_NONE)
+    {
+        switch (key)
+        {
+            case KEY_UP:
+            case KEY_DOWN:
+                return mAvatarList->handleKey(key, mask, called_from_parent);
+            case KEY_RETURN:
+            case KEY_TAB:
+                selectResident(mAvatarList->getSelectedUUID());
+                return true;
+            case KEY_ESCAPE:
+                LLChatMentionHelper::instance().hideHelper();
+                return true;
+            case KEY_LEFT:
+            case KEY_RIGHT:
+                return true;
+            default:
+                break;
+        }
+    }
+    return LLFloater::handleKey(key, mask, called_from_parent);
+}
+
+void LLFloaterChatMentionPicker::goneFromFront()
+{
+    LLChatMentionHelper::instance().hideHelper();
+}
+
+void LLFloaterChatMentionPicker::updateSessionID(LLUUID session_id)
+{
+    sSessionID = session_id;
+
+    LLParticipantList* item = dynamic_cast<LLParticipantList*>(LLFloaterIMContainer::getInstance()->getSessionModel(sSessionID));
+    if (!item)
+    {
+        LL_WARNS() << "Participant list is missing" << LL_ENDL;
+        return;
+    }
+
+    uuid_vec_t avatar_ids = getParticipantIds();
+    updateAvatarList(avatar_ids);
+}
+
+void LLFloaterChatMentionPicker::updateAvatarList(uuid_vec_t& avatar_ids)
+{
+    std::vector<std::string> av_names;
+    for (auto& id : avatar_ids)
+    {
+        LLAvatarName av_name;
+        LLAvatarNameCache::get(id, &av_name);
+        av_names.push_back(utf8str_tolower(av_name.getAccountName()));
+        av_names.push_back(utf8str_tolower(av_name.getDisplayName()));
+    }
+    LLChatMentionHelper::instance().updateAvatarList(av_names);
+}
diff --git a/indra/newview/llfloaterchatmentionpicker.h b/indra/newview/llfloaterchatmentionpicker.h
new file mode 100644
index 0000000000..8d221d7a89
--- /dev/null
+++ b/indra/newview/llfloaterchatmentionpicker.h
@@ -0,0 +1,58 @@
+/**
+ * @file llfloaterchatmentionpicker.h
+ *
+ * $LicenseInfo:firstyear=2025&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2025, Linden Research, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+#ifndef LLFLOATERCHATMENTIONPICKER_H
+#define LLFLOATERCHATMENTIONPICKER_H
+
+#include "llfloater.h"
+
+class LLAvatarList;
+
+class LLFloaterChatMentionPicker : public LLFloater
+{
+public:
+    LLFloaterChatMentionPicker(const LLSD& key);
+
+    virtual bool postBuild() override;
+    virtual void goneFromFront() override;
+
+    void buildAvatarList();
+
+    static uuid_vec_t getParticipantIds();
+    static void updateSessionID(LLUUID session_id);
+    static void updateAvatarList(uuid_vec_t& avatar_ids);
+
+private:
+
+    void onOpen(const LLSD& key) override;
+    void onClose(bool app_quitting) override;
+    virtual bool handleKey(KEY key, MASK mask, bool called_from_parent) override;
+    void selectResident(const LLUUID& id);
+
+    static LLUUID sSessionID;
+    LLAvatarList* mAvatarList;
+};
+
+#endif
diff --git a/indra/newview/llfloaterimnearbychat.cpp b/indra/newview/llfloaterimnearbychat.cpp
index db6f9ac22a..b649514bff 100644
--- a/indra/newview/llfloaterimnearbychat.cpp
+++ b/indra/newview/llfloaterimnearbychat.cpp
@@ -586,7 +586,7 @@ void LLFloaterIMNearbyChat::sendChat( EChatType type )
 {
     if (mInputEditor)
     {
-        LLWString text = mInputEditor->getWText();
+        LLWString text = mInputEditor->getConvertedText();
         LLWStringUtil::trim(text);
         LLWStringUtil::replaceChar(text,182,'\n'); // Convert paragraph symbols back into newlines.
         if (!text.empty())
diff --git a/indra/newview/llfloaterimsession.cpp b/indra/newview/llfloaterimsession.cpp
index 185274981b..84a9fad708 100644
--- a/indra/newview/llfloaterimsession.cpp
+++ b/indra/newview/llfloaterimsession.cpp
@@ -251,7 +251,7 @@ void LLFloaterIMSession::sendMsgFromInputEditor()
     {
         if (mInputEditor)
         {
-            LLWString text = mInputEditor->getWText();
+            LLWString text = mInputEditor->getConvertedText();
             LLWStringUtil::trim(text);
             LLWStringUtil::replaceChar(text,182,'\n'); // Convert paragraph symbols back into newlines.
             if(!text.empty())
diff --git a/indra/newview/llfloaterimsessiontab.cpp b/indra/newview/llfloaterimsessiontab.cpp
index 50e765c236..96aac8c1e6 100644
--- a/indra/newview/llfloaterimsessiontab.cpp
+++ b/indra/newview/llfloaterimsessiontab.cpp
@@ -35,6 +35,7 @@
 #include "llavatariconctrl.h"
 #include "llchatentry.h"
 #include "llchathistory.h"
+#include "llfloaterchatmentionpicker.h"
 #include "llchiclet.h"
 #include "llchicletbar.h"
 #include "lldraghandle.h"
@@ -485,6 +486,7 @@ void LLFloaterIMSessionTab::onFocusReceived()
         LLIMModel::instance().sendNoUnreadMessages(mSessionID);
     }
 
+    LLFloaterChatMentionPicker::updateSessionID(mSessionID);
     super::onFocusReceived();
 }
 
diff --git a/indra/newview/llpanelprofile.cpp b/indra/newview/llpanelprofile.cpp
index 08605f7cf4..c81746a48a 100644
--- a/indra/newview/llpanelprofile.cpp
+++ b/indra/newview/llpanelprofile.cpp
@@ -328,7 +328,7 @@ public:
         }
 
         const std::string verb = params[1].asString();
-        if (verb == "about")
+        if (verb == "about" || verb == "mention")
         {
             LLAvatarActions::showProfile(avatar_id);
             return true;
diff --git a/indra/newview/llstartup.cpp b/indra/newview/llstartup.cpp
index 3973036cc6..4f60f98b49 100644
--- a/indra/newview/llstartup.cpp
+++ b/indra/newview/llstartup.cpp
@@ -3566,7 +3566,7 @@ bool process_login_success_response()
 
     // Agent id needed for parcel info request in LLUrlEntryParcel
     // to resolve parcel name.
-    LLUrlEntryParcel::setAgentID(gAgentID);
+    LLUrlEntryBase::setAgentID(gAgentID);
 
     text = response["session_id"].asString();
     if(!text.empty()) gAgentSessionID.set(text);
diff --git a/indra/newview/llviewerchat.cpp b/indra/newview/llviewerchat.cpp
index 8b01c4ef88..2ca2c5c07d 100644
--- a/indra/newview/llviewerchat.cpp
+++ b/indra/newview/llviewerchat.cpp
@@ -36,6 +36,7 @@
 #include "llviewerregion.h"
 #include "llworld.h"
 #include "llinstantmessage.h" //SYSTEM_FROM
+#include "llurlregistry.h"
 
 // LLViewerChat
 LLViewerChat::font_change_signal_t LLViewerChat::sChatFontChangedSignal;
@@ -222,6 +223,13 @@ void LLViewerChat::formatChatMsg(const LLChat& chat, std::string& formated_msg)
 {
     std::string tmpmsg = chat.mText;
 
+    // show @name instead of slurl for chat mentions
+    LLUrlMatch match;
+    while (LLUrlRegistry::instance().findUrl(tmpmsg, match, LLUrlRegistryNullCallback, false, true))
+    {
+        tmpmsg.replace(match.getStart(), match.getEnd() - match.getStart() + 1, match.getLabel());
+    }
+
     if(chat.mChatStyle == CHAT_STYLE_IRC)
     {
         formated_msg = chat.mFromName + tmpmsg.substr(3);
diff --git a/indra/newview/llviewerfloaterreg.cpp b/indra/newview/llviewerfloaterreg.cpp
index 95c2a77ba8..4d9c2f3281 100644
--- a/indra/newview/llviewerfloaterreg.cpp
+++ b/indra/newview/llviewerfloaterreg.cpp
@@ -58,6 +58,7 @@
 #include "llfloatercamera.h"
 #include "llfloatercamerapresets.h"
 #include "llfloaterchangeitemthumbnail.h"
+#include "llfloaterchatmentionpicker.h"
 #include "llfloaterchatvoicevolume.h"
 #include "llfloaterclassified.h"
 #include "llfloaterconversationlog.h"
@@ -353,6 +354,7 @@ void LLViewerFloaterReg::registerFloaters()
     LLFloaterReg::add("chat_voice", "floater_voice_chat_volume.xml", (LLFloaterBuildFunc)&LLFloaterReg::build<LLFloaterChatVoiceVolume>);
     LLFloaterReg::add("change_item_thumbnail", "floater_change_item_thumbnail.xml", (LLFloaterBuildFunc)&LLFloaterReg::build<LLFloaterChangeItemThumbnail>);
     LLFloaterReg::add("nearby_chat", "floater_im_session.xml", (LLFloaterBuildFunc)&LLFloaterIMNearbyChat::buildFloater);
+    LLFloaterReg::add("chat_mention_picker", "floater_chat_mention_picker.xml", (LLFloaterBuildFunc)&LLFloaterReg::build<LLFloaterChatMentionPicker>);
     LLFloaterReg::add("classified", "floater_classified.xml", (LLFloaterBuildFunc)&LLFloaterReg::build<LLFloaterClassified>);
     LLFloaterReg::add("compile_queue", "floater_script_queue.xml", (LLFloaterBuildFunc)&LLFloaterReg::build<LLFloaterCompileQueue>);
     LLFloaterReg::add("conversation", "floater_conversation_log.xml", (LLFloaterBuildFunc)&LLFloaterReg::build<LLFloaterConversationLog>);
diff --git a/indra/newview/skins/default/colors.xml b/indra/newview/skins/default/colors.xml
index f0af4acf20..cb190d3d34 100644
--- a/indra/newview/skins/default/colors.xml
+++ b/indra/newview/skins/default/colors.xml
@@ -1000,4 +1000,10 @@
   <color
     name="OutfitSnapshotMacMask2"
     value="0.1 0.1 0.1 1"/>
+  <color
+    name="ChatMentionHighlight"
+    value="0.82 0.91 0.98 0.15" />
+  <color
+    name="ChatSelfMentionHighlight"
+    value="0.85 0.75 0.40 0.5" />
 </colors>
diff --git a/indra/newview/skins/default/xui/en/floater_chat_mention_picker.xml b/indra/newview/skins/default/xui/en/floater_chat_mention_picker.xml
new file mode 100644
index 0000000000..bbad99f932
--- /dev/null
+++ b/indra/newview/skins/default/xui/en/floater_chat_mention_picker.xml
@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="utf-8" standalone="yes" ?>
+<floater
+    name="chat_mention_picker"
+    title="CHOOSE RESIDENT"
+    single_instance="true"
+    can_minimize="false"
+    can_tear_off="false"
+    can_resize="true"
+    auto_close="true"
+    layout="topleft"
+    min_width="250"
+    chrome="true"
+    height="125"
+    width="310">
+   <avatar_list
+    allow_select="true"
+    follows="all"
+    height="120"
+    width="306"
+    ignore_online_status="true"
+    layout="topleft"
+    left="3"
+    keep_one_selected="true"
+    multi_select="false"
+    show_info_btn="false"
+    show_profile_btn="false"
+    show_speaking_indicator="false"
+    name="avatar_list"
+    right="-1"
+    top="2" />
+</floater>