feat: Refactor background sync to dynamically load Capacitor core and register plugin

src/app/components/message/layout/Base.tsx

@@ -35,6 +35,7 @@ export const MessageTextBody = as<'div', css.MessageTextBodyVariants & { notice?
       size="T400"
       priority={notice ? '300' : '400'}
       className={classNames(css.MessageTextBody({ preWrap, jumboEmoji, emote }), className)}
+      data-allow-text-selection="true"
       {...props}
       ref={ref}
     />

src/app/components/message/layout/layout.css.ts

@@ -215,6 +215,8 @@ export const MessageTextBody = recipe({
     overflow: 'clip',
     overflowY: 'clip',
     lineHeight: '1.5',
+    userSelect: 'text',
+    WebkitUserSelect: 'text',
   },
   variants: {
     preWrap: {

src/app/components/page/Page.tsx

@@ -60,10 +60,12 @@ export const PageNavHeader = as<'header', css.PageNavHeaderVariants>(
 
 export function PageNavContent({
   scrollRef,
+  scrollProps,
   children,
 }: {
   children: ReactNode;
   scrollRef?: MutableRefObject<HTMLDivElement | null>;
+  scrollProps?: React.ComponentProps<typeof Scroll>;
 }) {
   return (
     <Box grow="Yes" direction="Column">
@@ -74,6 +76,7 @@ export function PageNavContent({
         size="300"
         hideTrack
         visibility="Hover"
+        {...scrollProps}
       >
         <div className={css.PageNavContent}>{children}</div>
       </Scroll>

src/app/features/room/RoomTimeline.css.ts

@@ -1,5 +1,6 @@
+import { style } from '@vanilla-extract/css';
 import { RecipeVariants, recipe } from '@vanilla-extract/recipes';
-import { DefaultReset, config } from 'folds';
+import { DefaultReset, color, config, toRem } from 'folds';
 
 export const TimelineFloat = recipe({
   base: [
@@ -28,3 +29,81 @@ export const TimelineFloat = recipe({
 });
 
 export type TimelineFloatVariants = RecipeVariants<typeof TimelineFloat>;
+
+export const CarouselScroller = style([
+  DefaultReset,
+  {
+    display: 'flex',
+    gap: config.space.S200,
+    overflowX: 'auto',
+    overflowY: 'hidden',
+    paddingBottom: config.space.S100,
+    width: '100%',
+    cursor: 'grab',
+    userSelect: 'none',
+  },
+]);
+
+export const CarouselScrollerDragging = style([
+  DefaultReset,
+  {
+    cursor: 'grabbing',
+  },
+]);
+
+export const CarouselItem = style([
+  DefaultReset,
+  {
+    flex: '0 0 auto',
+    maxWidth: '100%',
+  },
+]);
+
+export const CarouselEdgeGradient = recipe({
+  base: [
+    DefaultReset,
+    {
+      position: 'absolute',
+      top: 0,
+      height: '100%',
+      width: toRem(16),
+      pointerEvents: 'none',
+      zIndex: 1,
+    },
+  ],
+  variants: {
+    position: {
+      Left: {
+        left: 0,
+        background: `linear-gradient(to right, ${color.Surface.Container}, rgba(116, 116, 116, 0))`,
+      },
+      Right: {
+        right: 0,
+        background: `linear-gradient(to left, ${color.Surface.Container}, rgba(116, 116, 116, 0))`,
+      },
+    },
+  },
+});
+
+export const CarouselScrollBtn = recipe({
+  base: [
+    DefaultReset,
+    {
+      position: 'absolute',
+      top: '50%',
+      zIndex: 2,
+    },
+  ],
+  variants: {
+    position: {
+      Left: {
+        left: 0,
+        transform: 'translate(-25%, -50%)',
+      },
+      Right: {
+        right: 0,
+        transform: 'translate(25%, -50%)',
+      },
+    },
+  },
+});

src/app/features/room/RoomTimeline.tsx

@@ -19,6 +19,7 @@ import {
   IContent,
   MatrixClient,
   MatrixEvent,
+  MsgType,
   Room,
   RoomEvent,
   RoomEventHandlerMap,
@@ -35,6 +36,7 @@ import {
   Chip,
   ContainerColor,
   Icon,
+  IconButton,
   Icons,
   Line,
   Scroll,
@@ -52,7 +54,7 @@ import { eventWithShortcode, factoryEventSentBy, getMxIdLocalPart } from '../../
 import { useMatrixClient } from '../../hooks/useMatrixClient';
 import { useVirtualPaginator, ItemRange } from '../../hooks/useVirtualPaginator';
 import { useAlive } from '../../hooks/useAlive';
-import { autoScrollToBottom, editableActiveElement } from '../../utils/dom';
+import { autoScrollToBottom, editableActiveElement, isScrolledToBottom } from '../../utils/dom';
 import {
   DefaultPlaceholder,
   CompactPlaceholder,
@@ -62,6 +64,7 @@ import {
   Time,
   MessageNotDecryptedContent,
   RedactedContent,
+  MImage,
   MSticker,
   ImageContent,
   EventContent,
@@ -110,6 +113,7 @@ import { useDocumentFocusChange } from '../../hooks/useDocumentFocusChange';
 import { RenderMessageContent } from '../../components/RenderMessageContent';
 import { Image } from '../../components/media';
 import { ImageViewer } from '../../components/image-viewer';
+import { useInertialHorizontalScroll } from '../../hooks/useInertialHorizontalScroll';
 import { roomToParentsAtom } from '../../state/room/roomToParents';
 import { useRoomUnread } from '../../state/hooks/unread';
 import { roomToUnreadAtom } from '../../state/room/roomToUnread';
@@ -134,6 +138,12 @@ import {
   useRoomWideEmbedFilters,
   combineEmbedFilters,
 } from '../../hooks/useRoomEmbedFilters';
+import {
+  IImageContent,
+  PAARROT_CAROUSEL_INDEX_PROPERTY_NAME,
+  PAARROT_CAROUSEL_TOTAL_PROPERTY_NAME,
+  PAARROT_CAROUSEL_UUID_PROPERTY_NAME,
+} from '../../../types/matrix/common';
 
 /** Information about a call member event for grouping */
 interface CallEventInfo {
@@ -146,6 +156,39 @@ interface CallEventInfo {
   mEvent: MatrixEvent;
 }
 
+interface CarouselEventMetadata {
+  uuid: string;
+  index: number;
+  total: number;
+  content: IImageContent;
+}
+
+interface CarouselRenderableEvent {
+  mEvent: MatrixEvent;
+  mEventId: string;
+  item: number;
+  content: IImageContent;
+  index: number;
+}
+
+const getCarouselEventMetadata = (mEvent: MatrixEvent): CarouselEventMetadata | undefined => {
+  if (mEvent.getType() !== MessageEvent.RoomMessage || mEvent.isRedacted()) {
+    return undefined;
+  }
+
+  const content = mEvent.getContent() as IImageContent;
+  const uuid = content[PAARROT_CAROUSEL_UUID_PROPERTY_NAME];
+  const index = content[PAARROT_CAROUSEL_INDEX_PROPERTY_NAME];
+  const total = content[PAARROT_CAROUSEL_TOTAL_PROPERTY_NAME];
+
+  if (content.msgtype !== MsgType.Image) return undefined;
+  if (typeof uuid !== 'string') return undefined;
+  if (typeof index !== 'number' || !Number.isInteger(index) || index < 0) return undefined;
+  if (typeof total !== 'number' || !Number.isInteger(total) || total < 1) return undefined;
+
+  return { uuid, index, total, content };
+};
+
 const TimelineFloat = as<'div', css.TimelineFloatVariants>(
   ({ position, className, ...props }, ref) => (
     <Box
@@ -169,6 +212,81 @@ const TimelineDivider = as<'div', { variant?: ContainerColor | 'Inherit' }>(
   )
 );
 
+type CarouselScrollerProps = {
+  children: React.ReactNode;
+};
+
+function CarouselScroller({ children }: CarouselScrollerProps) {
+  const {
+    scrollRef,
+    isDragging,
+    canScrollBack,
+    canScrollForward,
+    scrollBack,
+    scrollForward,
+    scrollProps,
+  } = useInertialHorizontalScroll();
+
+  return (
+    <Box style={{ position: 'relative' }}>
+      <Box
+        ref={scrollRef}
+        className={classNames(css.CarouselScroller, isDragging && css.CarouselScrollerDragging)}
+        {...scrollProps}
+      >
+        {children}
+      </Box>
+
+      {canScrollBack && (
+        <>
+          <div className={css.CarouselEdgeGradient({ position: 'Left' })} />
+          <IconButton
+            className={css.CarouselScrollBtn({ position: 'Left' })}
+            variant="Secondary"
+            radii="Pill"
+            size="300"
+            outlined
+            onClick={scrollBack}
+          >
+            <Icon size="300" src={Icons.ArrowLeft} />
+          </IconButton>
+        </>
+      )}
+
+      {canScrollForward && (
+        <>
+          <div className={css.CarouselEdgeGradient({ position: 'Right' })} />
+          <IconButton
+            className={css.CarouselScrollBtn({ position: 'Right' })}
+            variant="Primary"
+            radii="Pill"
+            size="300"
+            outlined
+            onClick={scrollForward}
+          >
+            <Icon size="300" src={Icons.ArrowRight} />
+          </IconButton>
+        </>
+      )}
+    </Box>
+  );
+}
+
+const getCarouselItemWidth = (content: IImageContent): string => {
+  const width = content.info?.w;
+  const height = content.info?.h;
+
+  if (!width || !height || height <= 0) {
+    return 'min(24rem, 72vw)';
+  }
+
+  const aspectRatio = width / height;
+  const baseHeightRem = 22;
+  const computedWidthRem = Math.max(11, Math.min(24, baseHeightRem * aspectRatio));
+
+  return `min(${computedWidthRem}rem, 72vw)`;
+};
+
 export const getLiveTimeline = (room: Room): EventTimeline =>
   room.getUnfilteredTimelineSet().getLiveTimeline();
 
@@ -651,7 +769,9 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
     useCallback(
       (mEvt: MatrixEvent) => {
         const isOwnMessage = mEvt.getSender() === mx.getUserId();
-        const shouldStickToBottom = atBottomRef.current || isOwnMessage;
+        const isBottomPinnedEvent =
+          mEvt.getType() === MessageEvent.RoomMessage || mEvt.getType() === MessageEvent.Sticker;
+        const shouldStickToBottom = atBottomRef.current || (isOwnMessage && isBottomPinnedEvent);
 
         // Always update timeline with new message
         setTimeline((ct) => ({
@@ -676,10 +796,12 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
           setUnreadInfo(getRoomUnreadInfo(room));
         }
 
-        // Preserve the pre-update bottom state so a newly added message keeps the view pinned.
+        // Preserve the pre-update bottom state so newly added chat messages keep the view pinned.
-        scrollToBottomRef.current.count += 1;
+        if (shouldStickToBottom) {
-        scrollToBottomRef.current.smooth = !isOwnMessage;
+          scrollToBottomRef.current.count += 1;
-        scrollToBottomRef.current.force = shouldStickToBottom;
+          scrollToBottomRef.current.smooth = !isOwnMessage;
+          scrollToBottomRef.current.force = true;
+        }
 
         // Show unread message preview for incoming messages when not at bottom
         if (!isOwnMessage && !atBottomRef.current) {
@@ -753,7 +875,7 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
         const scrollElement = getScrollElement();
         if (!editorBaseEntry || !scrollElement) return;
 
-        if (atBottomRef.current) {
+        if (isScrolledToBottom(scrollElement)) {
           autoScrollToBottom(scrollElement, false, true);
         }
       };
@@ -774,7 +896,7 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
       const previousHeight = timelineContentHeightRef.current;
       timelineContentHeightRef.current = nextHeight;
 
-      if (previousHeight === 0 || nextHeight <= previousHeight || !atBottomRef.current) {
+      if (previousHeight === 0 || nextHeight <= previousHeight || !isScrolledToBottom(scrollElement)) {
         return;
       }
 
@@ -1748,6 +1870,7 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
   let isPrevRendered = false;
   let newDivider = false;
   let dayDivider = false;
+  const groupedCarouselEventIds = new Set<string>();
 
   // Clear pending call events at the start of each render
   pendingCallEventsRef.current = [];
@@ -1869,6 +1992,110 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
     );
   };
 
+  const renderImageCarouselMessage = (
+    carouselEvents: CarouselRenderableEvent[],
+    mEventId: string,
+    mEvent: MatrixEvent,
+    item: number,
+    timelineSet: EventTimelineSet,
+    collapse: boolean
+  ): React.ReactNode => {
+    const reactionRelations = getEventReactions(timelineSet, mEventId);
+    const reactions = reactionRelations && reactionRelations.getSortedAnnotationsByKey();
+    const hasReactions = reactions && reactions.length > 0;
+    const { replyEventId, threadRootId } = mEvent;
+    const highlighted = focusItem?.index === item && focusItem.highlight;
+    const senderId = mEvent.getSender() ?? '';
+
+    const orderedCarouselEvents = [...carouselEvents].sort((a, b) => a.index - b.index);
+
+    return (
+      <Message
+        key={`carousel-${mEventId}`}
+        data-message-item={item}
+        data-message-id={mEventId}
+        room={room}
+        mEvent={mEvent}
+        messageSpacing={messageSpacing}
+        messageLayout={messageLayout}
+        collapse={collapse}
+        highlight={highlighted}
+        edit={editId === mEventId}
+        canDelete={canRedact || mEvent.getSender() === mx.getUserId()}
+        canSendReaction={canSendReaction}
+        canPinEvent={canPinEvent}
+        imagePackRooms={imagePackRooms}
+        relations={hasReactions ? reactionRelations : undefined}
+        onUserClick={handleUserClick}
+        onUsernameClick={handleUsernameClick}
+        onReplyClick={handleReplyClick}
+        onReactionToggle={handleReactionToggle}
+        onEditId={handleEdit}
+        reply={
+          replyEventId && (
+            <Reply
+              room={room}
+              timelineSet={timelineSet}
+              replyEventId={replyEventId}
+              threadRootId={threadRootId}
+              onClick={handleOpenReply}
+              onOpenThread={handleOpenThread}
+              getMemberPowerTag={getMemberPowerTag}
+              accessibleTagColors={accessiblePowerTagColors}
+              legacyUsernameColor={legacyUsernameColor || direct}
+            />
+          )
+        }
+        reactions={
+          reactionRelations && (
+            <Reactions
+              style={{ marginTop: config.space.S200 }}
+              room={room}
+              relations={reactionRelations}
+              mEventId={mEventId}
+              canSendReaction={canSendReaction}
+              onReactionToggle={handleReactionToggle}
+            />
+          )
+        }
+        hideReadReceipts={hideActivity}
+        showDeveloperTools={showDeveloperTools}
+        memberPowerTag={getMemberPowerTag(senderId)}
+        accessibleTagColors={accessiblePowerTagColors}
+        legacyUsernameColor={legacyUsernameColor || direct}
+        hour24Clock={hour24Clock}
+        dateFormatString={dateFormatString}
+      >
+        {mEvent.isRedacted() ? (
+          <RedactedContent reason={mEvent.getUnsigned().redacted_because?.content.reason} />
+        ) : (
+          <CarouselScroller>
+            {orderedCarouselEvents.map((carouselEvent) => (
+              <Box
+                key={carouselEvent.mEventId}
+                className={css.CarouselItem}
+                style={{ width: getCarouselItemWidth(carouselEvent.content) }}
+              >
+                <MImage
+                  content={carouselEvent.content}
+                  renderImageContent={(props) => (
+                    <ImageContent
+                      {...props}
+                      autoPlay={mediaAutoLoad}
+                      renderImage={(p) => <Image {...p} loading="lazy" />}
+                      renderViewer={(p) => <ImageViewer {...p} />}
+                    />
+                  )}
+                  outlined={messageLayout === MessageLayout.Bubble}
+                />
+              </Box>
+            ))}
+          </CarouselScroller>
+        )}
+      </Message>
+    );
+  };
+
   const eventRenderer = (item: number, index: number, allItems: number[]) => {
     const [eventTimeline, baseIndex] = getTimelineAndBaseIndex(timeline.linkedTimelines, item);
     if (!eventTimeline) return null;
@@ -1893,6 +2120,12 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
       dayDivider = prevEvent ? !inSameDay(prevEvent.getTs(), mEvent.getTs()) : false;
     }
 
+    if (groupedCarouselEventIds.has(mEventId)) {
+      prevEvent = mEvent;
+      isPrevRendered = true;
+      return null;
+    }
+
     const collapsed =
       isPrevRendered &&
       !dayDivider &&
@@ -1902,17 +2135,71 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
       prevEvent.getType() === mEvent.getType() &&
       minuteDifference(prevEvent.getTs(), mEvent.getTs()) < 2;
 
-    const rawEventJSX = reactionOrEditEvent(mEvent)
+    const getEventByItem = (
-      ? null
+      timelineItem: number
-      : renderMatrixEvent(
+    ): { event: MatrixEvent; eventId: string } | undefined => {
-          mEvent.getType(),
+      const [tm, bIndex] = getTimelineAndBaseIndex(timeline.linkedTimelines, timelineItem);
-          typeof mEvent.getStateKey() === 'string',
+      if (!tm) return undefined;
-          mEventId,
+
-          mEvent,
+      const event = getTimelineEvent(tm, getTimelineRelativeIndex(timelineItem, bIndex));
-          item,
+      const nextEventId = event?.getId();
-          timelineSet,
+      if (!event || !nextEventId) return undefined;
-          collapsed
+
-        );
+      return { event, eventId: nextEventId };
+    };
+
+    const carouselMetadata = getCarouselEventMetadata(mEvent);
+    const carouselEvents: CarouselRenderableEvent[] = [];
+    if (carouselMetadata && eventSender) {
+      carouselEvents.push({
+        mEvent,
+        mEventId,
+        item,
+        content: carouselMetadata.content,
+        index: carouselMetadata.index,
+      });
+
+      for (let nextIndex = index + 1; nextIndex < allItems.length; nextIndex += 1) {
+        const nextEvt = getEventByItem(allItems[nextIndex]);
+        if (!nextEvt) break;
+
+        const nextSender = nextEvt.event.getSender();
+        const nextMeta = getCarouselEventMetadata(nextEvt.event);
+
+        if (!nextMeta || nextSender !== eventSender || nextMeta.uuid !== carouselMetadata.uuid) {
+          break;
+        }
+
+        groupedCarouselEventIds.add(nextEvt.eventId);
+        carouselEvents.push({
+          mEvent: nextEvt.event,
+          mEventId: nextEvt.eventId,
+          item: allItems[nextIndex],
+          content: nextMeta.content,
+          index: nextMeta.index,
+        });
+
+        if (carouselEvents.length >= carouselMetadata.total) {
+          break;
+        }
+      }
+    }
+
+    let rawEventJSX: React.ReactNode = null;
+    if (!reactionOrEditEvent(mEvent)) {
+      rawEventJSX =
+        carouselEvents.length > 1
+          ? renderImageCarouselMessage(carouselEvents, mEventId, mEvent, item, timelineSet, collapsed)
+          : renderMatrixEvent(
+              mEvent.getType(),
+              typeof mEvent.getStateKey() === 'string',
+              mEventId,
+              mEvent,
+              item,
+              timelineSet,
+              collapsed
+            );
+    }
 
     // Check if this is a call event that should be grouped
     const isCallEventPending = rawEventJSX === ('CALL_EVENT_PENDING' as unknown as React.ReactNode);
@@ -2023,7 +2310,12 @@ export function RoomTimeline({ room, eventId, roomInputRef, editor }: RoomTimeli
           ref={timelineContentRef}
           direction="Column"
           justifyContent="End"
-          style={{ minHeight: '100%', padding: `${config.space.S600} 0` }}
+          style={{
+            minHeight: '100%',
+            padding: `${config.space.S600} 0`,
+            userSelect: 'none',
+            WebkitUserSelect: 'none',
+          }}
         >
           {!canPaginateBack && rangeAtStart && getItems().length > 0 && (
             <div

src/app/hooks/useInertialHorizontalScroll.ts

@@ -0,0 +1,397 @@
+import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
+import type {
+  MouseEvent as ReactMouseEvent,
+  PointerEvent as ReactPointerEvent,
+  RefObject,
+} from 'react';
+
+export type UseInertialHorizontalScrollOptions = {
+  axis?: 'x' | 'y';
+  scrollStepRatio?: number;
+  dragThreshold?: number;
+  friction?: number;
+  minVelocity?: number;
+};
+
+export type UseInertialHorizontalScrollResult = {
+  scrollRef: RefObject<HTMLDivElement>;
+  isDragging: boolean;
+  canScrollBack: boolean;
+  canScrollForward: boolean;
+  scrollBack: () => void;
+  scrollForward: () => void;
+  scrollProps: {
+    onPointerDown: (evt: ReactPointerEvent<HTMLDivElement>) => void;
+    onPointerMove: (evt: ReactPointerEvent<HTMLDivElement>) => void;
+    onPointerUp: (evt: ReactPointerEvent<HTMLDivElement>) => void;
+    onPointerCancel: (evt: ReactPointerEvent<HTMLDivElement>) => void;
+    onLostPointerCapture: (evt: ReactPointerEvent<HTMLDivElement>) => void;
+    onDragStartCapture: (evt: React.DragEvent<HTMLDivElement>) => void;
+    onClickCapture: (evt: ReactMouseEvent<HTMLDivElement>) => void;
+  };
+};
+
+const TEXT_SELECTION_TARGET_SELECTOR =
+  '[data-allow-text-selection="true"], input, textarea, [contenteditable="true"]';
+
+type ScrollState = {
+  activePointerId: number | null;
+  startPrimary: number;
+  startScrollPrimary: number;
+  lastPrimary: number;
+  lastTime: number;
+  velocity: number;
+  dragging: boolean;
+  moved: boolean;
+  suppressClick: boolean;
+  animationFrameId: number | null;
+};
+
+type PointerLikeEvent = {
+  pointerId: number;
+  clientX: number;
+  clientY: number;
+  timeStamp: number;
+  preventDefault?: () => void;
+};
+
+const DEFAULT_OPTIONS: Required<UseInertialHorizontalScrollOptions> = {
+  axis: 'x',
+  scrollStepRatio: 1.3,
+  dragThreshold: 3,
+  friction: 0.95,
+  minVelocity: 0.02,
+};
+
+/**
+ * Shared hook for drag-scrolling horizontal overflow areas with inertial momentum.
+ */
+export function useInertialHorizontalScroll(
+  options: UseInertialHorizontalScrollOptions = {}
+): UseInertialHorizontalScrollResult {
+  const resolvedOptions = useMemo(
+    () => ({ ...DEFAULT_OPTIONS, ...options }),
+    [options]
+  );
+
+  const scrollRef = useRef<HTMLDivElement>(null);
+  const stateRef = useRef<ScrollState>({
+    activePointerId: null,
+    startPrimary: 0,
+    startScrollPrimary: 0,
+    lastPrimary: 0,
+    lastTime: 0,
+    velocity: 0,
+    dragging: false,
+    moved: false,
+    suppressClick: false,
+    animationFrameId: null,
+  });
+  const [isDragging, setIsDragging] = useState(false);
+  const [canScrollBack, setCanScrollBack] = useState(false);
+  const [canScrollForward, setCanScrollForward] = useState(false);
+
+  const updateScrollState = useCallback(() => {
+    const scroll = scrollRef.current;
+    if (!scroll) return;
+
+    const isHorizontal = resolvedOptions.axis === 'x';
+    const scrollPrimary = isHorizontal ? scroll.scrollLeft : scroll.scrollTop;
+    const scrollSize = isHorizontal ? scroll.scrollWidth : scroll.scrollHeight;
+    const clientSize = isHorizontal ? scroll.clientWidth : scroll.clientHeight;
+    const maxScrollPrimary = Math.max(scrollSize - clientSize, 0);
+    setCanScrollBack(scrollPrimary > 1);
+    setCanScrollForward(scrollPrimary < maxScrollPrimary - 1);
+  }, [resolvedOptions.axis]);
+
+  useEffect(() => {
+    updateScrollState();
+
+    const scroll = scrollRef.current;
+    if (!scroll) return undefined;
+
+    const handleScroll = () => {
+      updateScrollState();
+    };
+
+    const handleResize = () => {
+      updateScrollState();
+    };
+
+    scroll.addEventListener('scroll', handleScroll, { passive: true });
+    window.addEventListener('resize', handleResize, { passive: true });
+
+    return () => {
+      scroll.removeEventListener('scroll', handleScroll);
+      window.removeEventListener('resize', handleResize);
+    };
+  }, [updateScrollState]);
+
+  useEffect(
+    () => () => {
+      const { animationFrameId } = stateRef.current;
+      if (animationFrameId !== null) {
+        cancelAnimationFrame(animationFrameId);
+      }
+    },
+    []
+  );
+
+  const scrollByStep = useCallback((direction: 1 | -1) => {
+    const scroll = scrollRef.current;
+    if (!scroll) return;
+
+    const isHorizontal = resolvedOptions.axis === 'x';
+    const currentPrimary = isHorizontal ? scroll.scrollLeft : scroll.scrollTop;
+    const offsetSize = isHorizontal ? scroll.offsetWidth : scroll.offsetHeight;
+    scroll.scrollTo({
+      ...(isHorizontal
+        ? { left: currentPrimary + offsetSize / resolvedOptions.scrollStepRatio * direction }
+        : { top: currentPrimary + offsetSize / resolvedOptions.scrollStepRatio * direction }),
+      behavior: 'smooth',
+    });
+  }, [resolvedOptions.axis, resolvedOptions.scrollStepRatio]);
+
+  const stopInertia = useCallback(() => {
+    const state = stateRef.current;
+    if (state.animationFrameId !== null) {
+      cancelAnimationFrame(state.animationFrameId);
+      state.animationFrameId = null;
+    }
+  }, []);
+
+  const startInertia = useCallback(() => {
+    const state = stateRef.current;
+    const scroll = scrollRef.current;
+    if (!scroll) return;
+    const isHorizontal = resolvedOptions.axis === 'x';
+
+    const step = (timestamp: number, previousTimestamp: number) => {
+      const currentState = stateRef.current;
+      const currentScroll = scrollRef.current;
+      if (!currentScroll) return;
+
+      const deltaMs = Math.max(timestamp - previousTimestamp, 1);
+      const deltaScroll = currentState.velocity * deltaMs;
+      if (Math.abs(currentState.velocity) < resolvedOptions.minVelocity) {
+        currentState.animationFrameId = null;
+        updateScrollState();
+        return;
+      }
+
+      const before = isHorizontal ? currentScroll.scrollLeft : currentScroll.scrollTop;
+      if (isHorizontal) {
+        currentScroll.scrollLeft = before - deltaScroll;
+      } else {
+        currentScroll.scrollTop = before - deltaScroll;
+      }
+      updateScrollState();
+
+      const after = isHorizontal ? currentScroll.scrollLeft : currentScroll.scrollTop;
+      if (after === before) {
+        currentState.animationFrameId = null;
+        return;
+      }
+
+      currentState.velocity *= Math.pow(resolvedOptions.friction, deltaMs / 16.6667);
+      currentState.animationFrameId = requestAnimationFrame((nextTimestamp) => step(nextTimestamp, timestamp));
+    };
+
+    stopInertia();
+    state.animationFrameId = requestAnimationFrame((timestamp) => step(timestamp, timestamp));
+  }, [resolvedOptions.axis, resolvedOptions.friction, resolvedOptions.minVelocity, stopInertia, updateScrollState]);
+
+  const endDrag = useCallback((pointerId: number | null) => {
+    const state = stateRef.current;
+    if (!state.dragging) return;
+
+    const scroll = scrollRef.current;
+    if (scroll && pointerId !== null && scroll.hasPointerCapture(pointerId)) {
+      scroll.releasePointerCapture(pointerId);
+    }
+
+    if (state.moved) {
+      state.suppressClick = true;
+      startInertia();
+    }
+
+    state.dragging = false;
+    state.activePointerId = null;
+    state.moved = false;
+    state.velocity = 0;
+    setIsDragging(false);
+  }, [startInertia]);
+
+  const processPointerMove = useCallback((evt: PointerLikeEvent) => {
+    const state = stateRef.current;
+    if (!state.dragging || state.activePointerId !== evt.pointerId) {
+      return;
+    }
+
+    const scroll = scrollRef.current;
+    if (!scroll) return;
+    const isHorizontal = resolvedOptions.axis === 'x';
+
+    const currentPrimary = isHorizontal ? evt.clientX : evt.clientY;
+    const deltaPrimary = currentPrimary - state.startPrimary;
+    const now = evt.timeStamp;
+    const deltaTime = Math.max(now - state.lastTime, 1);
+
+    if (Math.abs(deltaPrimary) >= resolvedOptions.dragThreshold) {
+      state.moved = true;
+    }
+
+    evt.preventDefault?.();
+
+    if (isHorizontal) {
+      scroll.scrollLeft = state.startScrollPrimary - deltaPrimary;
+    } else {
+      scroll.scrollTop = state.startScrollPrimary - deltaPrimary;
+    }
+
+    const rawVelocity = (currentPrimary - state.lastPrimary) / deltaTime;
+    state.velocity = Math.max(Math.min(rawVelocity, 2), -2);
+    state.lastPrimary = currentPrimary;
+    state.lastTime = now;
+  }, [resolvedOptions.axis, resolvedOptions.dragThreshold]);
+
+  const handlePointerDown = useCallback((evt: React.PointerEvent<HTMLDivElement>) => {
+    if (evt.button !== 0) return;
+    if (!evt.isPrimary) return;
+
+    const state = stateRef.current;
+    if (state.dragging && state.activePointerId === evt.pointerId) return;
+
+    const target = evt.target;
+    if (target instanceof Element && target.closest(TEXT_SELECTION_TARGET_SELECTOR)) {
+      return;
+    }
+
+    const scroll = scrollRef.current;
+    if (!scroll) return;
+    const isHorizontal = resolvedOptions.axis === 'x';
+
+    stopInertia();
+    evt.preventDefault();
+    evt.stopPropagation();
+
+    state.activePointerId = evt.pointerId;
+    state.startPrimary = isHorizontal ? evt.clientX : evt.clientY;
+    state.startScrollPrimary = isHorizontal ? scroll.scrollLeft : scroll.scrollTop;
+    state.lastPrimary = isHorizontal ? evt.clientX : evt.clientY;
+    state.lastTime = evt.timeStamp;
+    state.velocity = 0;
+    state.dragging = true;
+    state.moved = false;
+    state.suppressClick = false;
+
+    try {
+      scroll.setPointerCapture(evt.pointerId);
+    } catch {
+      // Ignore capture failures when browser has already ended pointer interaction.
+    }
+
+    setIsDragging(true);
+  }, [resolvedOptions.axis, stopInertia]);
+
+  const handlePointerMove = useCallback((evt: React.PointerEvent<HTMLDivElement>) => {
+    processPointerMove(evt);
+  }, [processPointerMove]);
+
+  const handlePointerUp = useCallback((evt: React.PointerEvent<HTMLDivElement>) => {
+    const state = stateRef.current;
+    if (state.activePointerId !== evt.pointerId) return;
+    endDrag(evt.pointerId);
+  }, [endDrag]);
+
+  const handlePointerCancel = useCallback((evt: React.PointerEvent<HTMLDivElement>) => {
+    const state = stateRef.current;
+    if (state.activePointerId !== evt.pointerId) return;
+    endDrag(evt.pointerId);
+  }, [endDrag]);
+
+  const handleLostPointerCapture = useCallback((evt: React.PointerEvent<HTMLDivElement>) => {
+    const state = stateRef.current;
+    if (state.activePointerId !== evt.pointerId) return;
+    endDrag(evt.pointerId);
+  }, [endDrag]);
+
+  useEffect(() => {
+    const handleWindowPointerMove = (evt: PointerEvent) => {
+      processPointerMove(evt);
+    };
+
+    const handleWindowPointerUpOrCancel = (evt: PointerEvent) => {
+      const state = stateRef.current;
+      if (state.activePointerId !== evt.pointerId) return;
+      endDrag(evt.pointerId);
+    };
+
+    window.addEventListener('pointermove', handleWindowPointerMove, true);
+    window.addEventListener('pointerup', handleWindowPointerUpOrCancel, true);
+    window.addEventListener('pointercancel', handleWindowPointerUpOrCancel, true);
+
+    return () => {
+      window.removeEventListener('pointermove', handleWindowPointerMove, true);
+      window.removeEventListener('pointerup', handleWindowPointerUpOrCancel, true);
+      window.removeEventListener('pointercancel', handleWindowPointerUpOrCancel, true);
+    };
+  }, [endDrag, processPointerMove]);
+
+  useEffect(() => {
+    const handleGlobalDragTermination = () => {
+      const state = stateRef.current;
+      if (!state.dragging) return;
+      endDrag(state.activePointerId);
+    };
+
+    const handleVisibilityChange = () => {
+      if (document.visibilityState !== 'visible') {
+        handleGlobalDragTermination();
+      }
+    };
+
+    window.addEventListener('mouseup', handleGlobalDragTermination, true);
+    window.addEventListener('pointerup', handleGlobalDragTermination, true);
+    window.addEventListener('blur', handleGlobalDragTermination, true);
+    document.addEventListener('visibilitychange', handleVisibilityChange, true);
+
+    return () => {
+      window.removeEventListener('mouseup', handleGlobalDragTermination, true);
+      window.removeEventListener('pointerup', handleGlobalDragTermination, true);
+      window.removeEventListener('blur', handleGlobalDragTermination, true);
+      document.removeEventListener('visibilitychange', handleVisibilityChange, true);
+    };
+  }, [endDrag]);
+
+  const handleClickCapture = useCallback((evt: React.MouseEvent<HTMLDivElement>) => {
+    const state = stateRef.current;
+    if (!state.suppressClick) return;
+
+    state.suppressClick = false;
+    evt.preventDefault();
+    evt.stopPropagation();
+  }, []);
+
+  const handleDragStartCapture = useCallback((evt: React.DragEvent<HTMLDivElement>) => {
+    evt.preventDefault();
+  }, []);
+
+  return {
+    scrollRef,
+    isDragging,
+    canScrollBack,
+    canScrollForward,
+    scrollBack: () => scrollByStep(-1),
+    scrollForward: () => scrollByStep(1),
+    scrollProps: {
+      onPointerDown: handlePointerDown,
+      onPointerMove: handlePointerMove,
+      onPointerUp: handlePointerUp,
+      onPointerCancel: handlePointerCancel,
+      onLostPointerCapture: handleLostPointerCapture,
+      onDragStartCapture: handleDragStartCapture,
+      onClickCapture: handleClickCapture,
+    },
+  };
+}

src/app/pages/client/direct/Direct.tsx

@@ -57,7 +57,7 @@ import {
 import { useDirectCreateSelected } from '../../../hooks/router/useDirectSelected';
 import { allInvitesAtom } from '../../../state/room-list/inviteList';
 import { UnreadBadge } from '../../../components/unread-badge';
-
+ 
 type DirectMenuProps = {
   requestClose: () => void;
 };
@@ -235,7 +235,6 @@ const DEFAULT_CATEGORY_ID = makeNavCategoryId('direct', 'direct');
 export function Direct() {
   const mx = useMatrixClient();
   useNavToActivePathMapper('direct');
-  const scrollRef = useRef<HTMLDivElement>(null);
   const directs = useDirectRooms();
   const notificationPreferences = useRoomsNotificationPreferencesContext();
   const roomToUnread = useAtomValue(roomToUnreadAtom);
@@ -246,6 +245,7 @@ export function Direct() {
   const selectedRoomId = useSelectedRoom();
   const noRoomToDisplay = directs.length === 0;
   const [closedCategories, setClosedCategories] = useAtom(useClosedNavCategoriesAtom());
+  const scrollRef = useRef<HTMLDivElement>(null);
   
   const reorderTrigger = useRoomListReorder(mx, directs);
 

src/app/utils/backgroundSync.ts

@@ -1,6 +1,13 @@
-import { Capacitor, registerPlugin, type PluginListenerHandle } from '@capacitor/core';
+import type { PluginListenerHandle } from '@capacitor/core';
 import type { IPusherRequest, MatrixClient } from 'matrix-js-sdk';
 
+const CAPACITOR_CORE_MODULE_ID = '@capacitor/core';
+
+type CapacitorCoreModule = typeof import('@capacitor/core');
+
+const loadCapacitorCore = async (): Promise<CapacitorCoreModule> =>
+  import(/* @vite-ignore */ CAPACITOR_CORE_MODULE_ID);
+
 type UnifiedPushStatus = {
   running: boolean;
   endpoint: string;
@@ -67,14 +74,15 @@ type StoredPusherState = {
   appId: string;
 };
 
-const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
 const DEFAULT_UNIFIED_PUSH_GATEWAY = 'https://matrix.gateway.unifiedpush.org/_matrix/push/v1/notify';
 const PUSHER_APP_ID_BASE = 'com.paarrot.app.android';
 const PUSHER_STORAGE_PREFIX = 'paarrot.unifiedpush';
 
 /** Returns true when the current platform is Android Capacitor. */
-export const isBackgroundSyncSupported = (): boolean =>
+export const isBackgroundSyncSupported = (): boolean => {
-  Capacitor.isNativePlatform() && Capacitor.getPlatform() === 'android';
+  const capacitor = (window as typeof window & { Capacitor?: CapacitorCoreModule['Capacitor'] }).Capacitor;
+  return Boolean(capacitor?.isNativePlatform?.() && capacitor.getPlatform() === 'android');
+};
 
 const getStoredPusherKey = (userId: string | null, deviceId: string | null): string =>
   `${PUSHER_STORAGE_PREFIX}:${userId ?? 'unknown'}:${deviceId ?? 'unknown'}`;
@@ -169,6 +177,9 @@ class AndroidUnifiedPushManager {
 
   /** Start native UnifiedPush registration and synchronize the Matrix pusher. */
   async start(mx: MatrixClient): Promise<void> {
+    const { Capacitor, registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
+
     console.log('[BackgroundSync] start() called, platform:', Capacitor.getPlatform(), 'isNative:', Capacitor.isNativePlatform());
     
     if (!isBackgroundSyncSupported()) {
@@ -216,6 +227,9 @@ class AndroidUnifiedPushManager {
   async stop(): Promise<void> {
     if (!isBackgroundSyncSupported()) return;
 
+    const { registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
+
     const client = this.client;
     if (client) {
       const deviceId = client.getDeviceId();
@@ -280,6 +294,8 @@ class AndroidUnifiedPushManager {
   /** Re-opens distributor selection once after ACTION_REQUIRED and logs actionable status. */
   private async tryRequestDistributorSetup(): Promise<void> {
     try {
+      const { registerPlugin } = await loadCapacitorCore();
+      const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
       const setupResult = await MatrixBackgroundSync.requestDistributorSetup();
       console.warn('[BackgroundSync] requestDistributorSetup result:', setupResult);
       const status = await this.safeGetStatus();
@@ -335,6 +351,9 @@ class AndroidUnifiedPushManager {
   private async ensureListeners(): Promise<void> {
     if (this.listenersReady) return;
 
+    const { registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
+
     this.listenerHandles = [
       await MatrixBackgroundSync.addListener('unifiedPushNewEndpoint', (event) => {
         void this.handleNewEndpoint(event).catch((err) => {
@@ -363,6 +382,9 @@ class AndroidUnifiedPushManager {
     const client = this.client;
     if (!client) return;
 
+    const { registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
+
     const status = await this.safeGetStatus();
     console.log('[BackgroundSync] Native status before pusher sync:', status);
     if (status?.registered && status.endpoint) {
@@ -435,6 +457,8 @@ class AndroidUnifiedPushManager {
   /** Read native registration state without failing the caller. */
   private async safeGetStatus(): Promise<UnifiedPushStatus | undefined> {
     try {
+      const { registerPlugin } = await loadCapacitorCore();
+      const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
       return await MatrixBackgroundSync.getStatus();
     } catch (err) {
       console.warn('[BackgroundSync] Failed to read UnifiedPush status:', err);
@@ -458,6 +482,8 @@ export const triggerBackgroundSyncPing = async (reason?: string): Promise<void>
   if (!isBackgroundSyncSupported()) return;
 
   try {
+    const { registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
     await MatrixBackgroundSync.triggerPing({ reason });
   } catch (err) {
     console.warn('[BackgroundSync] triggerPing failed:', err);
@@ -479,6 +505,8 @@ export const setAppForegroundState = async (foreground: boolean): Promise<void>
   if (!isBackgroundSyncSupported()) return;
 
   try {
+    const { registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
     await MatrixBackgroundSync.setAppForeground({ foreground });
   } catch (err) {
     console.warn('[BackgroundSync] setAppForeground failed:', err);
@@ -497,6 +525,8 @@ export const requestResetPushRegistration = async (): Promise<{ success: boolean
   }
 
   try {
+    const { registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
     const result = await MatrixBackgroundSync.requestDistributorSetup();
     console.log('[BackgroundSync] requestDistributorSetup completed:', result);
     return result ?? { success: false };
@@ -510,6 +540,8 @@ export const requestResetPushRegistration = async (): Promise<{ success: boolean
 export const getBackgroundSyncStatus = async (): Promise<UnifiedPushStatus | undefined> => {
   if (!isBackgroundSyncSupported()) return undefined;
   try {
+    const { registerPlugin } = await loadCapacitorCore();
+    const MatrixBackgroundSync = registerPlugin<MatrixBackgroundSyncPlugin>('MatrixBackgroundSync');
     return await MatrixBackgroundSync.getStatus();
   } catch (err) {
     console.warn('[BackgroundSync] getStatus failed:', err);

src/app/utils/tauri.ts

@@ -119,6 +119,17 @@ let notificationTapCallback: ((path: string) => void) | null = null;
 const ANDROID_NOTIFICATION_SMALL_ICON = 'ic_stat_paarrot';
 const ANDROID_NOTIFICATION_ICON_COLOR = '#FF8A00';
 
+const CAPACITOR_LOCAL_NOTIFICATIONS_MODULE_ID = '@capacitor/local-notifications';
+
+type CapacitorLocalNotificationsModule = typeof import('@capacitor/local-notifications');
+
+/**
+ * Lazy-load Capacitor local notifications at runtime only.
+ * Vite must not pre-resolve this module because some desktop builds do not include it.
+ */
+const importCapacitorLocalNotifications = async (): Promise<CapacitorLocalNotificationsModule> =>
+  import(/* @vite-ignore */ CAPACITOR_LOCAL_NOTIFICATIONS_MODULE_ID);
+
 /**
  * Bring the Tauri window to the front and focus it
  */
@@ -196,7 +207,7 @@ export const setupNotificationTapListener = async (onTap: (path: string) => void
 
   if (isCapacitorNative()) {
     try {
-      const { LocalNotifications } = await import('@capacitor/local-notifications');
+      const { LocalNotifications } = await importCapacitorLocalNotifications();
       await LocalNotifications.addListener('localNotificationActionPerformed', async (event: any) => {
         await focusWindow();
         const path = event?.notification?.extra?.path;
@@ -336,7 +347,7 @@ const ensureCapacitorNotificationChannel = async (): Promise<void> => {
   if (notificationChannelCreated || !isAndroid()) return;
 
   try {
-    const { LocalNotifications } = await import('@capacitor/local-notifications');
+    const { LocalNotifications } = await importCapacitorLocalNotifications();
     await LocalNotifications.createChannel({
       id: 'messages',
       name: 'Messages',
@@ -365,7 +376,7 @@ export const requestSystemNotificationPermission = async (): Promise<boolean> =>
 
   if (isCapacitorNative()) {
     try {
-      const { LocalNotifications } = await import('@capacitor/local-notifications');
+      const { LocalNotifications } = await importCapacitorLocalNotifications();
       let perm = await LocalNotifications.checkPermissions();
       if (perm.display !== 'granted') {
         perm = await LocalNotifications.requestPermissions();
@@ -385,7 +396,7 @@ export const requestSystemNotificationPermission = async (): Promise<boolean> =>
 export const getSystemNotificationPermissionState = async (): Promise<PermissionState> => {
   if (isCapacitorNative()) {
     try {
-      const { LocalNotifications } = await import('@capacitor/local-notifications');
+      const { LocalNotifications } = await importCapacitorLocalNotifications();
       const perm = await LocalNotifications.checkPermissions();
       return perm.display === 'granted' ? 'granted' : 'prompt';
     } catch (err) {
@@ -471,7 +482,7 @@ export const sendNotification = async (options: {
 
   if (isCapacitorNative()) {
     try {
-      const { LocalNotifications } = await import('@capacitor/local-notifications');
+      const { LocalNotifications } = await importCapacitorLocalNotifications();
       let perm = await LocalNotifications.checkPermissions();
       if (perm.display !== 'granted') {
         perm = await LocalNotifications.requestPermissions();

src/types/matrix/common.ts

@@ -4,6 +4,9 @@ import { MsgType } from 'matrix-js-sdk';
 export const MATRIX_BLUR_HASH_PROPERTY_NAME = 'xyz.amorgan.blurhash';
 export const MATRIX_SPOILER_PROPERTY_NAME = 'page.codeberg.everypizza.msc4193.spoiler';
 export const MATRIX_SPOILER_REASON_PROPERTY_NAME = 'page.codeberg.everypizza.msc4193.spoiler.reason';
+export const PAARROT_CAROUSEL_UUID_PROPERTY_NAME = 'com.paarrot.carousel_uuid';
+export const PAARROT_CAROUSEL_INDEX_PROPERTY_NAME = 'com.paarrot.carousel_index';
+export const PAARROT_CAROUSEL_TOTAL_PROPERTY_NAME = 'com.paarrot.carousel_total';
 
 export type IImageInfo = {
   w?: number;
@@ -51,6 +54,9 @@ export type IImageContent = {
   file?: IEncryptedFile;
   [MATRIX_SPOILER_PROPERTY_NAME]?: boolean;
   [MATRIX_SPOILER_REASON_PROPERTY_NAME]?: string;
+  [PAARROT_CAROUSEL_UUID_PROPERTY_NAME]?: string;
+  [PAARROT_CAROUSEL_INDEX_PROPERTY_NAME]?: number;
+  [PAARROT_CAROUSEL_TOTAL_PROPERTY_NAME]?: number;
 };
 
 export type IVideoContent = {