web/timeline: omit profile on consecutive messages from same sender

web/src/ui/timeline/TimelineEvent.css

@@ -33,15 +33,40 @@ div.timeline-event {
 		}
 	}
 
+	> div.event-time-only {
+		grid-area: timestamp;
+		display: none;
+		align-items: end;
+		justify-content: center;
+		font-size: .8rem;
+		max-height: 1.25rem;
+		margin-right: .25rem;
+	}
+
 	> div.event-content {
 		grid-area: content;
 		overflow: hidden;
 	}
 
+	&.same-sender {
+		grid-template:
+			"timestamp content" auto
+			/ 2.75rem 1fr;
+		margin-top: 0;
+
+		> div.sender-avatar, > div.event-sender-and-time {
+			display: none;
+		}
+
+		> div.event-time-only {
+			display: flex;
+		}
+	}
+
 	&.hidden-event {
 		grid-template:
-			"sender avatar content" auto
-			/ 2.5rem 1.5rem 1fr;
+			"timestamp avatar content" auto
+			/ 2.75rem 1.5rem 1fr;
 		margin-top: 0;
 
 		> div.sender-avatar {
@@ -58,9 +83,11 @@ div.timeline-event {
 		}
 
 		> div.event-sender-and-time {
-			> span.event-sender, > span.event-edited {
-				display: none;
-			}
+			display: none;
+		}
+
+		> div.event-time-only {
+			display: flex;
 		}
 	}
 }

web/src/ui/timeline/TimelineEvent.tsx

@@ -27,6 +27,7 @@ import "./TimelineEvent.css"
 export interface TimelineEventProps {
 	room: RoomStateStore
 	evt: MemDBEvent
+	prevEvt: MemDBEvent | null
 }
 
 function getBodyType(evt: MemDBEvent): React.FunctionComponent<EventContentProps> {
@@ -61,13 +62,22 @@ const EventReactions = ({ reactions }: { reactions: Record<string, number> }) =>
 	</div>
 }
 
-const TimelineEvent = ({ room, evt }: TimelineEventProps) => {
+const TimelineEvent = ({ room, evt, prevEvt }: TimelineEventProps) => {
 	const memberEvt = room.getStateEvent("m.room.member", evt.sender)
 	const memberEvtContent = memberEvt?.content as MemberEventContent | undefined
 	const BodyType = getBodyType(evt)
 	const eventTS = new Date(evt.timestamp)
 	const editEventTS = evt.last_edit ? new Date(evt.last_edit.timestamp) : null
-	return <div className={`timeline-event ${BodyType === HiddenEvent ? "hidden-event" : ""}`}>
+	const wrapperClassNames = ["timeline-event"]
+	if (BodyType === HiddenEvent) {
+		wrapperClassNames.push("hidden-event")
+	} else if (prevEvt?.sender === evt.sender && getBodyType(prevEvt) !== HiddenEvent) {
+		wrapperClassNames.push("same-sender")
+	}
+	const fullTime = fullTimeFormatter.format(eventTS)
+	const shortTime = formatShortTime(eventTS)
+	const editTime = editEventTS ? `Edited at ${fullTimeFormatter.format(editEventTS)}` : null
+	return <div className={wrapperClassNames.join(" ")}>
 		<div className="sender-avatar" title={evt.sender}>
 			<img
 				className="avatar"
@@ -78,11 +88,14 @@ const TimelineEvent = ({ room, evt }: TimelineEventProps) => {
 		</div>
 		<div className="event-sender-and-time">
 			<span className="event-sender">{memberEvtContent?.displayname ?? evt.sender}</span>
-			<span className="event-time" title={fullTimeFormatter.format(eventTS)}>{formatShortTime(eventTS)}</span>
-			{editEventTS ? <span className="event-edited" title={`Edited at ${fullTimeFormatter.format(editEventTS)}`}>
+			<span className="event-time" title={fullTime}>{shortTime}</span>
+			{(editEventTS && editTime) ? <span className="event-edited" title={editTime}>
 				(edited at {formatShortTime(editEventTS)})
 			</span> : null}
 		</div>
+		<div className="event-time-only">
+			<span className="event-time" title={editTime ? `${fullTime} - ${editTime}` : fullTime}>{shortTime}</span>
+		</div>
 		<div className="event-content">
 			<BodyType room={room} event={evt}/>
 			{evt.reactions ? <EventReactions reactions={evt.reactions}/> : null}

web/src/ui/timeline/TimelineView.tsx

@@ -15,6 +15,7 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 import { use, useCallback, useEffect, useRef } from "react"
 import { RoomStateStore, useRoomTimeline } from "../../api/statestore.ts"
+import { MemDBEvent } from "../../api/types"
 import { ClientContext } from "../ClientContext.ts"
 import TimelineEvent from "./TimelineEvent.tsx"
 import "./TimelineView.css"
@@ -80,15 +81,23 @@ const TimelineView = ({ room }: TimelineViewProps) => {
 		return () => observer.unobserve(topElem)
 	}, [loadHistory, topRef])
 
+	let prevEvt: MemDBEvent | null = null
 	return <div className="timeline-view" onScroll={handleScroll} ref={timelineViewRef}>
 		<div className="timeline-beginning">
 			<button onClick={loadHistory}>Load history</button>
 		</div>
 		<div className="timeline-list">
 			<div className="timeline-top-ref" ref={topRef}/>
-			{timeline.map(entry => entry ? <TimelineEvent
-				key={entry.rowid} room={room} evt={entry}
-			/> : null)}
+			{timeline.map(entry => {
+				if (!entry) {
+					return null
+				}
+				const thisEvt = <TimelineEvent
+					key={entry.rowid} room={room} evt={entry} prevEvt={prevEvt}
+				/>
+				prevEvt = entry
+				return thisEvt
+			})}
 			<div className="timeline-bottom-ref" ref={bottomRef}/>
 		</div>
 	</div>