Fix time placeholder showing on mobile format for condensed messages

As an extra, make sure time placeholder cannot be selected anymore, and do not do an extra call to `tz` helper when time is not relevant/displayed.

I tried to entirely remove `time`/`from` blocks, but because of flexbox layout, that broke message alignment...

client/css/style.css

@@ -837,6 +837,10 @@ kbd {
 	display: none;
 }
 
+#chat .condensed .time {
+	visibility: hidden;
+}
+
 #windows .header .topic,
 .messages .msg,
 .sidebar {
@@ -2043,6 +2047,11 @@ part/quit messages where we don't load previews (adds a blank line otherwise) */
 		padding: 0;
 	}
 
+	#chat .condensed .time,
+	#chat .condensed .from {
+		display: none;
+	}
+
 	#chat .date-marker,
 	#chat .unread-marker {
 		margin: 0;
@@ -2181,7 +2190,3 @@ part/quit messages where we don't load previews (adds a blank line otherwise) */
 #chat table.channel-list .topic {
 	white-space: pre-wrap;
 }
-
-.hide-text {
-	color: transparent !important;
-}

client/views/msg_condensed.tpl

@@ -1,5 +1,5 @@
-<div class="msg {{type}} closed" data-time="{{time}}">
-	<span class="time hide-text">{{tz time}}</span>
+<div class="msg condensed closed" data-time="{{time}}">
+	<span class="time">{{tz time}}</span>
 	<span class="from"></span>
 	<span class="content">
 		<span class="condensed-text"></span>