Merge branch 'develop' into t3chguy/eslint

res/css/_components.scss

@@ -201,6 +201,7 @@
 @import "./views/rooms/_EditMessageComposer.scss";
 @import "./views/rooms/_EntityTile.scss";
 @import "./views/rooms/_EventTile.scss";
+@import "./views/rooms/_EventBubbleTile.scss";
 @import "./views/rooms/_GroupLayout.scss";
 @import "./views/rooms/_IRCLayout.scss";
 @import "./views/rooms/_JumpToBottomButton.scss";

res/css/views/avatars/_BaseAvatar.scss

@@ -27,6 +27,7 @@ limitations under the License.
     // https://bugzilla.mozilla.org/show_bug.cgi?id=255139
     display: inline-block;
     user-select: none;
+    line-height: 1;
 }
 
 .mx_BaseAvatar_initial {

res/css/views/messages/_MImageBody.scss

@@ -18,7 +18,6 @@ $timelineImageBorderRadius: 4px;
 
 .mx_MImageBody {
     display: block;
-    margin-right: 34px;
 }
 
 .mx_MImageBody_thumbnail {
@@ -29,6 +28,10 @@ $timelineImageBorderRadius: 4px;
     top: 0;
     border-radius: $timelineImageBorderRadius;
 
+    display: flex;
+    justify-content: center;
+    align-items: center;
+
     > canvas {
         border-radius: $timelineImageBorderRadius;
     }
@@ -43,17 +46,6 @@ $timelineImageBorderRadius: 4px;
     position: relative;
 }
 
-.mx_MImageBody_thumbnail_spinner {
-    position: absolute;
-    left: 50%;
-    top: 50%;
-}
-
-// Inner img should be centered around 0, 0
-.mx_MImageBody_thumbnail_spinner > * {
-    transform: translate(-50%, -50%);
-}
-
 .mx_MImageBody_gifLabel {
     position: absolute;
     display: block;

res/css/views/messages/_ReactionsRow.scss

@@ -26,6 +26,7 @@ limitations under the License.
         height: 24px;
         vertical-align: middle;
         margin-left: 4px;
+        margin-right: 4px;
 
         &::before {
             content: '';

res/css/views/rooms/_EventBubbleTile.scss

@@ -0,0 +1,323 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+.mx_EventTile[data-layout=bubble],
+.mx_EventTile[data-layout=bubble] ~ .mx_EventListSummary {
+    --avatarSize: 32px;
+    --gutterSize: 11px;
+    --cornerRadius: 12px;
+    --maxWidth: 70%;
+}
+
+.mx_EventTile[data-layout=bubble] {
+
+    position: relative;
+    margin-top: var(--gutterSize);
+    margin-left: 50px;
+    margin-right: 100px;
+
+    &.mx_EventTile_continuation {
+        margin-top: 2px;
+    }
+
+    /* For replies */
+    .mx_EventTile {
+        padding-top: 0;
+    }
+
+    &:hover {
+        &::before {
+            content: '';
+            position: absolute;
+            top: -1px;
+            bottom: -1px;
+            left: -60px;
+            right: -60px;
+            z-index: -1;
+            background: $eventbubble-bg-hover;
+            border-radius: 4px;
+        }
+
+        .mx_EventTile_avatar {
+            img {
+                box-shadow: 0 0 0 3px $eventbubble-bg-hover;
+            }
+        }
+    }
+
+    .mx_SenderProfile,
+    .mx_EventTile_line {
+        width: fit-content;
+        max-width: 70%;
+    }
+
+    .mx_SenderProfile {
+        position: relative;
+        top: -2px;
+        left: 2px;
+    }
+
+    &[data-self=false] {
+        .mx_EventTile_line {
+            border-bottom-right-radius: var(--cornerRadius);
+        }
+        .mx_EventTile_avatar {
+            left: -34px;
+        }
+
+        .mx_MessageActionBar {
+            right: 0;
+            transform: translate3d(50%, 50%, 0);
+        }
+
+        --backgroundColor: $eventbubble-others-bg;
+    }
+    &[data-self=true] {
+        .mx_EventTile_line {
+            border-bottom-left-radius: var(--cornerRadius);
+            float: right;
+            > a {
+                left: auto;
+                right: -48px;
+            }
+        }
+        .mx_SenderProfile {
+            display: none;
+        }
+        .mx_ReactionsRow {
+            float: right;
+            clear: right;
+            display: flex;
+
+            /* Moving the "add reaction button" before the reactions */
+            > :last-child {
+                order: -1;
+            }
+        }
+        .mx_EventTile_avatar {
+            top: -19px; // height of the sender block
+            right: -35px;
+        }
+
+        --backgroundColor: $eventbubble-self-bg;
+    }
+
+    .mx_EventTile_line {
+        position: relative;
+        padding: var(--gutterSize);
+        border-top-left-radius: var(--cornerRadius);
+        border-top-right-radius: var(--cornerRadius);
+        background: var(--backgroundColor);
+        display: flex;
+        gap: 5px;
+        margin: 0 -12px 0 -9px;
+        > a {
+            position: absolute;
+            left: -48px;
+        }
+    }
+
+    &.mx_EventTile_continuation[data-self=false] .mx_EventTile_line {
+        border-top-left-radius: 0;
+    }
+    &.mx_EventTile_lastInSection[data-self=false] .mx_EventTile_line {
+        border-bottom-left-radius: var(--cornerRadius);
+    }
+
+    &.mx_EventTile_continuation[data-self=true] .mx_EventTile_line {
+        border-top-right-radius: 0;
+    }
+    &.mx_EventTile_lastInSection[data-self=true] .mx_EventTile_line {
+        border-bottom-right-radius: var(--cornerRadius);
+    }
+
+    .mx_EventTile_avatar {
+        position: absolute;
+        top: 0;
+        line-height: 1;
+        img {
+            box-shadow: 0 0 0 3px $eventbubble-avatar-outline;
+            border-radius: 50%;
+        }
+    }
+
+    &[data-has-reply=true] {
+        > .mx_EventTile_line {
+            flex-direction: column;
+        }
+
+        .mx_ReplyThread_show {
+            order: 99999;
+        }
+
+        .mx_ReplyThread {
+            margin: 0 calc(-1 * var(--gutterSize));
+
+            .mx_EventTile_reply {
+                max-width: 90%;
+                padding: 0;
+                > a {
+                    display: none !important;
+                }
+            }
+
+            .mx_EventTile {
+                display: flex;
+                gap: var(--gutterSize);
+                .mx_EventTile_avatar {
+                    position: static;
+                }
+                .mx_SenderProfile {
+                    display: none;
+                }
+            }
+        }
+    }
+
+    .mx_EditMessageComposer_buttons {
+        position: static;
+        padding: 0;
+        margin: 0;
+        background: transparent;
+    }
+
+    .mx_ReactionsRow {
+        margin-right: -18px;
+        margin-left: -9px;
+    }
+
+    .mx_ReplyThread {
+        border-left-width: 2px;
+        border-left-color: $eventbubble-reply-color;
+    }
+
+    &.mx_EventTile_bubbleContainer,
+    &.mx_EventTile_info,
+    & ~ .mx_EventListSummary[data-expanded=false] {
+        --backgroundColor: transparent;
+        --gutterSize: 0;
+
+        display: flex;
+        align-items: center;
+        justify-content: center;
+
+        .mx_EventTile_avatar {
+            position: static;
+            order: -1;
+            margin-right: 5px;
+        }
+    }
+
+    & ~ .mx_EventListSummary {
+        --maxWidth: 80%;
+        margin-left: calc(var(--avatarSize) + var(--gutterSize));
+        margin-right: calc(var(--gutterSize) + var(--avatarSize));
+        .mx_EventListSummary_toggle {
+            float: none;
+            margin: 0;
+            order: 9;
+            margin-left: 5px;
+        }
+        .mx_EventListSummary_avatars {
+            padding-top: 0;
+        }
+
+        &::after {
+            content: "";
+            clear: both;
+        }
+
+        .mx_EventTile {
+            margin: 0 6px;
+        }
+
+        .mx_EventTile_line {
+            margin: 0 5px;
+            > a {
+                left: auto;
+                right: 0;
+                transform: translateX(calc(100% + 5px));
+            }
+        }
+
+        .mx_MessageActionBar {
+            transform: translate3d(50%, 0, 0);
+        }
+    }
+
+    & ~ .mx_EventListSummary[data-expanded=false] {
+        padding: 0 34px;
+    }
+
+    /* events that do not require bubble layout */
+    & ~ .mx_EventListSummary,
+    &.mx_EventTile_bad {
+        .mx_EventTile_line {
+            background: transparent;
+        }
+
+        &:hover {
+            &::before {
+                background: transparent;
+            }
+        }
+    }
+
+    & + .mx_EventListSummary {
+        .mx_EventTile {
+            margin-top: 0;
+            padding: 0;
+        }
+    }
+
+    .mx_EventListSummary_toggle {
+        margin-right: 55px;
+    }
+
+    /* Special layout scenario for "Unable To Decrypt (UTD)" events */
+    &.mx_EventTile_bad > .mx_EventTile_line {
+        display: grid;
+        grid-template:
+            "reply reply" auto
+            "shield body" auto
+            "shield link" auto
+            / auto  1fr;
+        .mx_EventTile_e2eIcon {
+            grid-area: shield;
+        }
+        .mx_UnknownBody {
+            grid-area: body;
+        }
+        .mx_EventTile_keyRequestInfo {
+            grid-area: link;
+        }
+        .mx_ReplyThread_wrapper {
+            grid-area: reply;
+        }
+    }
+
+
+    .mx_EventTile_readAvatars {
+        position: absolute;
+        right: -110px;
+        bottom: 0;
+        top: auto;
+    }
+
+    .mx_MTextBody {
+        max-width: 100%;
+    }
+}

res/css/views/rooms/_EventTile.scss

@@ -1,6 +1,6 @@
 /*
 Copyright 2015, 2016 OpenMarket Ltd
-Copyright 2020 The Matrix.org Foundation C.I.C.
+Copyright 2020-2021 The Matrix.org Foundation C.I.C.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -18,102 +18,305 @@ limitations under the License.
 $left-gutter: 64px;
 $hover-select-border: 4px;
 
-.mx_EventTile {
+.mx_EventTile:not([data-layout=bubble]) {
     max-width: 100%;
     clear: both;
     padding-top: 18px;
     font-size: $font-14px;
     position: relative;
-}
 
-.mx_EventTile.mx_EventTile_info {
+    &.mx_EventTile_info {
-    padding-top: 1px;
+        padding-top: 1px;
-}
+    }
 
-.mx_EventTile_avatar {
+    .mx_EventTile_avatar {
-    top: 14px;
+        top: 14px;
-    left: 8px;
+        left: 8px;
-    cursor: pointer;
+        cursor: pointer;
-    user-select: none;
+        user-select: none;
-}
+    }
 
-.mx_EventTile.mx_EventTile_info .mx_EventTile_avatar {
+    &.mx_EventTile_info .mx_EventTile_avatar {
-    top: $font-6px;
+        top: $font-6px;
-    left: $left-gutter;
+        left: $left-gutter;
-}
+    }
 
-.mx_EventTile_continuation {
+    &.mx_EventTile_continuation {
-    padding-top: 0px !important;
+        padding-top: 0px !important;
+
+        &.mx_EventTile_isEditing {
+            padding-top: 5px !important;
+            margin-top: -5px;
+        }
+    }
 
     &.mx_EventTile_isEditing {
-        padding-top: 5px !important;
+        background-color: $header-panel-bg-color;
-        margin-top: -5px;
     }
-}
 
-.mx_EventTile_isEditing {
+    .mx_SenderProfile {
-    background-color: $header-panel-bg-color;
+        color: $primary-fg-color;
-}
+        font-size: $font-14px;
+        display: inline-block; /* anti-zalgo, with overflow hidden */
+        overflow: hidden;
+        cursor: pointer;
+        padding-bottom: 0px;
+        padding-top: 0px;
+        margin: 0px;
+        /* the next three lines, along with overflow hidden, truncate long display names */
+        white-space: nowrap;
+        text-overflow: ellipsis;
+        max-width: calc(100% - $left-gutter);
+    }
 
-.mx_EventTile .mx_SenderProfile {
+    .mx_SenderProfile .mx_Flair {
-    color: $primary-fg-color;
+        opacity: 0.7;
-    font-size: $font-14px;
+        margin-left: 5px;
-    display: inline-block; /* anti-zalgo, with overflow hidden */
+        display: inline-block;
-    overflow: hidden;
+        vertical-align: top;
-    cursor: pointer;
+        overflow: hidden;
-    padding-bottom: 0px;
+        user-select: none;
-    padding-top: 0px;
-    margin: 0px;
-    /* the next three lines, along with overflow hidden, truncate long display names */
-    white-space: nowrap;
-    text-overflow: ellipsis;
-    max-width: calc(100% - $left-gutter);
-}
 
-.mx_EventTile .mx_SenderProfile .mx_Flair {
+        img {
-    opacity: 0.7;
+            vertical-align: -2px;
-    margin-left: 5px;
+            margin-right: 2px;
-    display: inline-block;
+            border-radius: 8px;
-    vertical-align: top;
+        }
-    overflow: hidden;
+    }
-    user-select: none;
 
-    img {
+    &.mx_EventTile_isEditing .mx_MessageTimestamp {
-        vertical-align: -2px;
+        visibility: hidden;
-        margin-right: 2px;
+    }
+
+    .mx_MessageTimestamp {
+        display: block;
+        white-space: nowrap;
+        left: 0px;
+        text-align: center;
+        user-select: none;
+    }
+
+    &.mx_EventTile_continuation .mx_EventTile_line {
+        clear: both;
+    }
+
+    .mx_EventTile_line, .mx_EventTile_reply {
+        position: relative;
+        padding-left: $left-gutter;
         border-radius: 8px;
     }
-}
 
-.mx_EventTile_isEditing .mx_MessageTimestamp {
+    .mx_EventTile_reply {
-    visibility: hidden;
+        margin-right: 10px;
-}
-
-.mx_EventTile .mx_MessageTimestamp {
-    display: block;
-    white-space: nowrap;
-    left: 0px;
-    text-align: center;
-    user-select: none;
-}
-
-.mx_EventTile_continuation .mx_EventTile_line {
-    clear: both;
-}
-
-.mx_EventTile_line, .mx_EventTile_reply {
-    position: relative;
-    padding-left: $left-gutter;
-    border-radius: 8px;
-}
-
-.mx_RoomView_timeline_rr_enabled,
-// on ELS we need the margin to allow interaction with the expand/collapse button which is normally in the RR gutter
-.mx_EventListSummary {
-    .mx_EventTile_line {
-        /* ideally should be 100px, but 95px gives us a max thumbnail size of 800x600, which is nice */
-        margin-right: 110px;
     }
+
+    &.mx_EventTile_selected > div > a > .mx_MessageTimestamp {
+        left: calc(-$hover-select-border);
+    }
+
+    /* this is used for the tile for the event which is selected via the URL.
+     * TODO: ultimately we probably want some transition on here.
+     */
+    &.mx_EventTile_selected > .mx_EventTile_line {
+        border-left: $accent-color 4px solid;
+        padding-left: calc($left-gutter - $hover-select-border);
+        background-color: $event-selected-color;
+    }
+
+    &.mx_EventTile_highlight,
+    &.mx_EventTile_highlight .markdown-body {
+        color: $event-highlight-fg-color;
+
+        .mx_EventTile_line {
+            background-color: $event-highlight-bg-color;
+        }
+    }
+
+    &.mx_EventTile_info .mx_EventTile_line {
+        padding-left: calc($left-gutter + 18px);
+    }
+
+    &.mx_EventTile_selected.mx_EventTile_info .mx_EventTile_line {
+        padding-left: calc($left-gutter + 18px - $hover-select-border);
+    }
+
+    &.mx_EventTile:hover .mx_EventTile_line,
+    &.mx_EventTile.mx_EventTile_actionBarFocused .mx_EventTile_line,
+    &.mx_EventTile.focus-visible:focus-within .mx_EventTile_line {
+        background-color: $event-selected-color;
+    }
+
+    .mx_EventTile_searchHighlight {
+        background-color: $accent-color;
+        color: $accent-fg-color;
+        border-radius: 5px;
+        padding-left: 2px;
+        padding-right: 2px;
+        cursor: pointer;
+    }
+
+    .mx_EventTile_searchHighlight a {
+        background-color: $accent-color;
+        color: $accent-fg-color;
+    }
+
+    .mx_EventTile_receiptSent,
+    .mx_EventTile_receiptSending {
+        // We don't use `position: relative` on the element because then it won't line
+        // up with the other read receipts
+
+        &::before {
+            background-color: $tertiary-fg-color;
+            mask-repeat: no-repeat;
+            mask-position: center;
+            mask-size: 14px;
+            width: 14px;
+            height: 14px;
+            content: '';
+            position: absolute;
+            top: 0;
+            left: 0;
+            right: 0;
+        }
+    }
+    .mx_EventTile_receiptSent::before {
+        mask-image: url('$(res)/img/element-icons/circle-sent.svg');
+    }
+    .mx_EventTile_receiptSending::before {
+        mask-image: url('$(res)/img/element-icons/circle-sending.svg');
+    }
+
+    &.mx_EventTile_contextual {
+        opacity: 0.4;
+    }
+
+    .mx_EventTile_msgOption {
+        float: right;
+        text-align: right;
+        position: relative;
+        width: 90px;
+
+        /* Hack to stop the height of this pushing the messages apart.
+           Replaces margin-top: -6px. This interacts better with a read
+           marker being in between. Content overflows. */
+        height: 1px;
+
+        margin-right: 10px;
+    }
+
+    .mx_EventTile_msgOption a {
+        text-decoration: none;
+    }
+
+    /* all the overflow-y: hidden; are to trap Zalgos -
+       but they introduce an implicit overflow-x: auto.
+       so make that explicitly hidden too to avoid random
+       horizontal scrollbars occasionally appearing, like in
+       https://github.com/vector-im/vector-web/issues/1154
+        */
+    .mx_EventTile_content {
+        display: block;
+        overflow-y: hidden;
+        overflow-x: hidden;
+        margin-right: 34px;
+    }
+
+    /* De-zalgoing */
+    .mx_EventTile_body {
+        overflow-y: hidden;
+    }
+
+    /* Spoiler stuff */
+    .mx_EventTile_spoiler {
+        cursor: pointer;
+    }
+
+    .mx_EventTile_spoiler_reason {
+        color: $event-timestamp-color;
+        font-size: $font-11px;
+    }
+
+    .mx_EventTile_spoiler_content {
+        filter: blur(5px) saturate(0.1) sepia(1);
+        transition-duration: 0.5s;
+    }
+
+    .mx_EventTile_spoiler.visible > .mx_EventTile_spoiler_content {
+        filter: none;
+    }
+
+    &:hover.mx_EventTile_verified .mx_EventTile_line,
+    &:hover.mx_EventTile_unverified .mx_EventTile_line,
+    &:hover.mx_EventTile_unknown .mx_EventTile_line {
+        padding-left: calc($left-gutter - $hover-select-border);
+    }
+
+    &:hover.mx_EventTile_verified .mx_EventTile_line {
+        border-left: $e2e-verified-color $EventTile_e2e_state_indicator_width solid;
+    }
+
+    &:hover.mx_EventTile_unverified .mx_EventTile_line {
+        border-left: $e2e-unverified-color $EventTile_e2e_state_indicator_width solid;
+    }
+
+    &:hover.mx_EventTile_unknown .mx_EventTile_line {
+        border-left: $e2e-unknown-color $EventTile_e2e_state_indicator_width solid;
+    }
+
+    &:hover.mx_EventTile_verified.mx_EventTile_info .mx_EventTile_line,
+    &:hover.mx_EventTile_unverified.mx_EventTile_info .mx_EventTile_line,
+    &:hover.mx_EventTile_unknown.mx_EventTile_info .mx_EventTile_line {
+        padding-left: calc($left-gutter + 18px - $hover-select-border);
+    }
+
+    /* End to end encryption stuff */
+    &:hover .mx_EventTile_e2eIcon {
+        opacity: 1;
+    }
+
+    // Explicit relationships so that it doesn't apply to nested EventTile components (e.g in Replies)
+    &:hover.mx_EventTile_verified .mx_EventTile_line > a > .mx_MessageTimestamp,
+    &:hover.mx_EventTile_unverified .mx_EventTile_line > a > .mx_MessageTimestamp,
+    &:hover.mx_EventTile_unknown .mx_EventTile_line > a > .mx_MessageTimestamp {
+        left: calc(-$hover-select-border);
+    }
+
+    // Explicit relationships so that it doesn't apply to nested EventTile components (e.g in Replies)
+    &:hover.mx_EventTile_verified .mx_EventTile_line > .mx_EventTile_e2eIcon,
+    &:hover.mx_EventTile_unverified .mx_EventTile_line > .mx_EventTile_e2eIcon,
+    &:hover.mx_EventTile_unknown .mx_EventTile_line > .mx_EventTile_e2eIcon {
+        display: block;
+        left: 41px;
+    }
+
+    .mx_MImageBody {
+        margin-right: 34px;
+    }
+
+    .mx_EventTile_e2eIcon {
+        position: absolute;
+        top: 6px;
+        left: 44px;
+        bottom: 0;
+        right: 0;
+    }
+
+    .mx_ReactionsRow {
+        margin: 0;
+        padding: 6px 60px;
+    }
+}
+
+.mx_RoomView_timeline_rr_enabled {
+
+    .mx_EventTile:not([data-layout=bubble]) {
+        .mx_EventTile_line {
+            /* ideally should be 100px, but 95px gives us a max thumbnail size of 800x600, which is nice */
+            margin-right: 110px;
+        }
+    }
+
+    // on ELS we need the margin to allow interaction with the expand/collapse button which is normally in the RR gutter
 }
 
 .mx_EventTile_bubbleContainer {
@@ -132,121 +335,6 @@ $hover-select-border: 4px;
     }
 }
 
-.mx_EventTile_reply {
-    margin-right: 10px;
-}
-
-/* HACK to override line-height which is already marked important elsewhere */
-.mx_EventTile_bigEmoji.mx_EventTile_bigEmoji {
-    font-size: 48px !important;
-    line-height: 57px !important;
-}
-
-.mx_EventTile_selected > div > a > .mx_MessageTimestamp {
-    left: calc(-$hover-select-border);
-}
-
-.mx_EventTile:hover .mx_MessageActionBar,
-.mx_EventTile.mx_EventTile_actionBarFocused .mx_MessageActionBar,
-[data-whatinput='keyboard'] .mx_EventTile:focus-within .mx_MessageActionBar,
-.mx_EventTile.focus-visible:focus-within .mx_MessageActionBar {
-    visibility: visible;
-}
-
-/* this is used for the tile for the event which is selected via the URL.
- * TODO: ultimately we probably want some transition on here.
- */
-.mx_EventTile_selected > .mx_EventTile_line {
-    border-left: $accent-color 4px solid;
-    padding-left: calc($left-gutter - $hover-select-border);
-    background-color: $event-selected-color;
-}
-
-.mx_EventTile_highlight,
-.mx_EventTile_highlight .markdown-body {
-    color: $event-highlight-fg-color;
-
-    .mx_EventTile_line {
-        background-color: $event-highlight-bg-color;
-    }
-}
-
-.mx_EventTile_info .mx_EventTile_line {
-    padding-left: calc($left-gutter + 18px);
-}
-
-.mx_EventTile_selected.mx_EventTile_info .mx_EventTile_line {
-    padding-left: calc($left-gutter + 18px - $hover-select-border);
-}
-
-.mx_EventTile:hover .mx_EventTile_line,
-.mx_EventTile.mx_EventTile_actionBarFocused .mx_EventTile_line,
-.mx_EventTile.focus-visible:focus-within .mx_EventTile_line {
-    background-color: $event-selected-color;
-}
-
-.mx_EventTile_searchHighlight {
-    background-color: $accent-color;
-    color: $accent-fg-color;
-    border-radius: 5px;
-    padding-left: 2px;
-    padding-right: 2px;
-    cursor: pointer;
-}
-
-.mx_EventTile_searchHighlight a {
-    background-color: $accent-color;
-    color: $accent-fg-color;
-}
-
-.mx_EventTile_receiptSent,
-.mx_EventTile_receiptSending {
-    // We don't use `position: relative` on the element because then it won't line
-    // up with the other read receipts
-
-    &::before {
-        background-color: $tertiary-fg-color;
-        mask-repeat: no-repeat;
-        mask-position: center;
-        mask-size: 14px;
-        width: 14px;
-        height: 14px;
-        content: '';
-        position: absolute;
-        top: 0;
-        left: 0;
-        right: 0;
-    }
-}
-.mx_EventTile_receiptSent::before {
-    mask-image: url('$(res)/img/element-icons/circle-sent.svg');
-}
-.mx_EventTile_receiptSending::before {
-    mask-image: url('$(res)/img/element-icons/circle-sending.svg');
-}
-
-.mx_EventTile_contextual {
-    opacity: 0.4;
-}
-
-.mx_EventTile_msgOption {
-    float: right;
-    text-align: right;
-    position: relative;
-    width: 90px;
-
-    /* Hack to stop the height of this pushing the messages apart.
-       Replaces margin-top: -6px. This interacts better with a read
-       marker being in between. Content overflows. */
-    height: 1px;
-
-    margin-right: 10px;
-}
-
-.mx_EventTile_msgOption a {
-    text-decoration: none;
-}
-
 .mx_EventTile_readAvatars {
     position: relative;
     display: inline-block;
@@ -277,52 +365,27 @@ $hover-select-border: 4px;
     position: absolute;
 }
 
-/* all the overflow-y: hidden; are to trap Zalgos -
+/* HACK to override line-height which is already marked important elsewhere */
-   but they introduce an implicit overflow-x: auto.
+.mx_EventTile_bigEmoji.mx_EventTile_bigEmoji {
-   so make that explicitly hidden too to avoid random
+    font-size: 48px !important;
-   horizontal scrollbars occasionally appearing, like in
+    line-height: 57px !important;
-   https://github.com/vector-im/vector-web/issues/1154
-    */
-.mx_EventTile_content {
-    display: block;
-    overflow-y: hidden;
-    overflow-x: hidden;
-    margin-right: 34px;
 }
 
-/* De-zalgoing */
+.mx_EventTile_content .mx_EventTile_edited {
-.mx_EventTile_body {
+    user-select: none;
-    overflow-y: hidden;
+    font-size: $font-12px;
-}
+    color: $roomtopic-color;
-
+    display: inline-block;
-/* Spoiler stuff */
+    margin-left: 9px;
-.mx_EventTile_spoiler {
     cursor: pointer;
 }
 
-.mx_EventTile_spoiler_reason {
-    color: $event-timestamp-color;
-    font-size: $font-11px;
-}
-
-.mx_EventTile_spoiler_content {
-    filter: blur(5px) saturate(0.1) sepia(1);
-    transition-duration: 0.5s;
-}
-
-.mx_EventTile_spoiler.visible > .mx_EventTile_spoiler_content {
-    filter: none;
-}
 
 .mx_EventTile_e2eIcon {
-    position: absolute;
+    position: relative;
-    top: 6px;
-    left: 44px;
     width: 14px;
     height: 14px;
     display: block;
-    bottom: 0;
-    right: 0;
     opacity: 0.2;
     background-repeat: no-repeat;
     background-size: contain;
@@ -381,87 +444,6 @@ $hover-select-border: 4px;
     opacity: 1;
 }
 
-.mx_EventTile_keyRequestInfo {
-    font-size: $font-12px;
-}
-
-.mx_EventTile_keyRequestInfo_text {
-    opacity: 0.5;
-}
-
-.mx_EventTile_keyRequestInfo_text a {
-    color: $primary-fg-color;
-    text-decoration: underline;
-    cursor: pointer;
-}
-
-.mx_EventTile_keyRequestInfo_tooltip_contents p {
-    text-align: auto;
-    margin-left: 3px;
-    margin-right: 3px;
-}
-
-.mx_EventTile_keyRequestInfo_tooltip_contents p:first-child {
-    margin-top: 0px;
-}
-
-.mx_EventTile_keyRequestInfo_tooltip_contents p:last-child {
-    margin-bottom: 0px;
-}
-
-.mx_EventTile:hover.mx_EventTile_verified .mx_EventTile_line,
-.mx_EventTile:hover.mx_EventTile_unverified .mx_EventTile_line,
-.mx_EventTile:hover.mx_EventTile_unknown .mx_EventTile_line {
-    padding-left: calc($left-gutter - $hover-select-border);
-}
-
-.mx_EventTile:hover.mx_EventTile_verified .mx_EventTile_line {
-    border-left: $e2e-verified-color $EventTile_e2e_state_indicator_width solid;
-}
-
-.mx_EventTile:hover.mx_EventTile_unverified .mx_EventTile_line {
-    border-left: $e2e-unverified-color $EventTile_e2e_state_indicator_width solid;
-}
-
-.mx_EventTile:hover.mx_EventTile_unknown .mx_EventTile_line {
-    border-left: $e2e-unknown-color $EventTile_e2e_state_indicator_width solid;
-}
-
-.mx_EventTile:hover.mx_EventTile_verified.mx_EventTile_info .mx_EventTile_line,
-.mx_EventTile:hover.mx_EventTile_unverified.mx_EventTile_info .mx_EventTile_line,
-.mx_EventTile:hover.mx_EventTile_unknown.mx_EventTile_info .mx_EventTile_line {
-    padding-left: calc($left-gutter + 18px - $hover-select-border);
-}
-
-/* End to end encryption stuff */
-.mx_EventTile:hover .mx_EventTile_e2eIcon {
-    opacity: 1;
-}
-
-// Explicit relationships so that it doesn't apply to nested EventTile components (e.g in Replies)
-.mx_EventTile:hover.mx_EventTile_verified .mx_EventTile_line > a > .mx_MessageTimestamp,
-.mx_EventTile:hover.mx_EventTile_unverified .mx_EventTile_line > a > .mx_MessageTimestamp,
-.mx_EventTile:hover.mx_EventTile_unknown .mx_EventTile_line > a > .mx_MessageTimestamp {
-    left: calc(-$hover-select-border);
-}
-
-// Explicit relationships so that it doesn't apply to nested EventTile components (e.g in Replies)
-.mx_EventTile:hover.mx_EventTile_verified .mx_EventTile_line > .mx_EventTile_e2eIcon,
-.mx_EventTile:hover.mx_EventTile_unverified .mx_EventTile_line > .mx_EventTile_e2eIcon,
-.mx_EventTile:hover.mx_EventTile_unknown .mx_EventTile_line > .mx_EventTile_e2eIcon {
-    display: block;
-    left: 41px;
-}
-
-.mx_EventTile_content .mx_EventTile_edited {
-    user-select: none;
-    font-size: $font-12px;
-    color: $roomtopic-color;
-    display: inline-block;
-    margin-left: 9px;
-    cursor: pointer;
-}
-
 /* Various markdown overrides */
 
 .mx_EventTile_body pre {
@@ -595,6 +577,35 @@ $hover-select-border: 4px;
 
 /* end of overrides */
 
+
+.mx_EventTile_keyRequestInfo {
+    font-size: $font-12px;
+}
+
+.mx_EventTile_keyRequestInfo_text {
+    opacity: 0.5;
+}
+
+.mx_EventTile_keyRequestInfo_text a {
+    color: $primary-fg-color;
+    text-decoration: underline;
+    cursor: pointer;
+}
+
+.mx_EventTile_keyRequestInfo_tooltip_contents p {
+    text-align: auto;
+    margin-left: 3px;
+    margin-right: 3px;
+}
+
+.mx_EventTile_keyRequestInfo_tooltip_contents p:first-child {
+    margin-top: 0px;
+}
+
+.mx_EventTile_keyRequestInfo_tooltip_contents p:last-child {
+    margin-bottom: 0px;
+}
+
 .mx_EventTile_tileError {
     color: red;
     text-align: center;
@@ -615,6 +626,13 @@ $hover-select-border: 4px;
     }
 }
 
+.mx_EventTile:hover .mx_MessageActionBar,
+.mx_EventTile.mx_EventTile_actionBarFocused .mx_MessageActionBar,
+[data-whatinput='keyboard'] .mx_EventTile:focus-within .mx_MessageActionBar,
+.mx_EventTile.focus-visible:focus-within .mx_MessageActionBar {
+    visibility: visible;
+}
+
 @media only screen and (max-width: 480px) {
     .mx_EventTile_line, .mx_EventTile_reply {
         padding-left: 0;

res/themes/dark/css/_dark.scss

@@ -227,6 +227,13 @@ $groupFilterPanel-background-blur-amount: 30px;
 
 $composer-shadow-color: rgba(0, 0, 0, 0.28);
 
+// Bubble tiles
+$eventbubble-self-bg: #143A34;
+$eventbubble-others-bg: #394049;
+$eventbubble-bg-hover: #433C23;
+$eventbubble-avatar-outline: $bg-color;
+$eventbubble-reply-color: #C1C6CD;
+
 // ***** Mixins! *****
 
 @define-mixin mx_DialogButton {

res/themes/legacy-light/css/_legacy-light.scss

@@ -347,6 +347,13 @@ $appearance-tab-border-color: $input-darker-bg-color;
 
 $composer-shadow-color: tranparent;
 
+// Bubble tiles
+$eventbubble-self-bg: #F8FDFC;
+$eventbubble-others-bg: #F7F8F9;
+$eventbubble-bg-hover: rgb(242, 242, 242);
+$eventbubble-avatar-outline: #fff;
+$eventbubble-reply-color: #C1C6CD;
+
 // ***** Mixins! *****
 
 @define-mixin mx_DialogButton {

res/themes/light/css/_light.scss

@@ -349,6 +349,13 @@ $groupFilterPanel-background-blur-amount: 20px;
 
 $composer-shadow-color: rgba(0, 0, 0, 0.04);
 
+// Bubble tiles
+$eventbubble-self-bg: #F8FDFC;
+$eventbubble-others-bg: #F7F8F9;
+$eventbubble-bg-hover: #FEFCF5;
+$eventbubble-avatar-outline: $primary-bg-color;
+$eventbubble-reply-color: #C1C6CD;
+
 // ***** Mixins! *****
 
 @define-mixin mx_DialogButton {

src/components/structures/MessagePanel.tsx

@@ -653,8 +653,10 @@ export default class MessagePanel extends React.Component<IProps, IState> {
         }
 
         let willWantDateSeparator = false;
+        let lastInSection = true;
         if (nextEvent) {
             willWantDateSeparator = this.wantsDateSeparator(mxEv, nextEvent.getDate() || new Date());
+            lastInSection = willWantDateSeparator || mxEv.getSender() !== nextEvent.getSender();
         }
 
         // is this a continuation of the previous message?
@@ -712,7 +714,7 @@ export default class MessagePanel extends React.Component<IProps, IState> {
                     isTwelveHour={this.props.isTwelveHour}
                     permalinkCreator={this.props.permalinkCreator}
                     last={last}
-                    lastInSection={willWantDateSeparator}
+                    lastInSection={lastInSection}
                     lastSuccessful={isLastSuccessful}
                     isSelectedEvent={highlight}
                     getRelationsForEvent={this.props.getRelationsForEvent}
@@ -720,6 +722,7 @@ export default class MessagePanel extends React.Component<IProps, IState> {
                     layout={this.props.layout}
                     enableFlair={this.props.enableFlair}
                     showReadReceipts={this.props.showReadReceipts}
+                    hideSender={this.props.room.getMembers().length <= 2 && this.props.layout === Layout.Bubble}
                 />
             </TileErrorBoundary>,
         );

src/components/views/elements/EventListSummary.tsx

@@ -63,7 +63,7 @@ const EventListSummary: React.FC<IProps> = ({
     // If we are only given few events then just pass them through
     if (events.length < threshold) {
         return (
-            <li className="mx_EventListSummary" data-scroll-tokens={eventIds}>
+            <li className="mx_EventListSummary" data-scroll-tokens={eventIds} data-expanded={true}>
                 { children }
             </li>
         );
@@ -92,7 +92,7 @@ const EventListSummary: React.FC<IProps> = ({
     }
 
     return (
-        <li className="mx_EventListSummary" data-scroll-tokens={eventIds}>
+        <li className="mx_EventListSummary" data-scroll-tokens={eventIds} data-expanded={expanded + ""}>
             <AccessibleButton className="mx_EventListSummary_toggle" onClick={toggleExpanded} aria-expanded={expanded}>
                 { expanded ? _t('collapse') : _t('expand') }
             </AccessibleButton>
@@ -101,4 +101,8 @@ const EventListSummary: React.FC<IProps> = ({
     );
 };
 
+EventListSummary.defaultProps = {
+    startExpanded: false,
+};
+
 export default EventListSummary;

src/components/views/messages/MImageBody.tsx

@@ -433,9 +433,9 @@ export default class MImageBody extends React.Component<IProps, IState> {
     protected getPlaceholder(width: number, height: number): JSX.Element {
         const blurhash = this.props.mxEvent.getContent().info[BLURHASH_FIELD];
         if (blurhash) return <Blurhash hash={blurhash} width={width} height={height} />;
-        return <div className="mx_MImageBody_thumbnail_spinner">
+        return (
             <InlineSpinner w={32} h={32} />
-        </div>;
+        );
     }
 
     // Overidden by MStickerBody

src/components/views/messages/UnknownBody.tsx

@@ -16,12 +16,19 @@ limitations under the License.
 */
 
 import React, { forwardRef } from "react";
+import { MatrixEvent } from "matrix-js-sdk/src";
 
-export default forwardRef(({ mxEvent }, ref) => {
+interface IProps {
+    mxEvent: MatrixEvent;
+    children?: React.ReactNode;
+}
+
+export default forwardRef(({ mxEvent, children }: IProps, ref: React.RefObject<HTMLSpanElement>) => {
     const text = mxEvent.getContent().body;
     return (
         <span className="mx_UnknownBody" ref={ref}>
             { text }
+            { children }
         </span>
     );
 });

src/components/views/rooms/EventTile.tsx

@@ -170,8 +170,6 @@ export function getHandlerTile(ev) {
     return eventTileTypes[type];
 }
 
-const MAX_READ_AVATARS = 5;
-
 // Our component structure for EventTiles on the timeline is:
 //
 // .-EventTile------------------------------------------------.
@@ -297,6 +295,9 @@ interface IProps {
 
     // whether or not to always show timestamps
     alwaysShowTimestamps?: boolean;
+
+    // whether or not to display the sender
+    hideSender?: boolean;
 }
 
 interface IState {
@@ -656,6 +657,10 @@ export default class EventTile extends React.Component<IProps, IState> {
             return <SentReceipt messageState={this.props.mxEvent.getAssociatedStatus()} />;
         }
 
+        const MAX_READ_AVATARS = this.props.layout == Layout.Bubble
+            ? 2
+            : 5;
+
         // return early if there are no read receipts
         if (!this.props.readReceipts || this.props.readReceipts.length === 0) {
             // We currently must include `mx_EventTile_readAvatars` in the DOM
@@ -951,7 +956,7 @@ export default class EventTile extends React.Component<IProps, IState> {
             );
         }
 
-        if (needsSenderProfile) {
+        if (needsSenderProfile && this.props.hideSender !== true) {
             if (!this.props.tileShape) {
                 sender = <SenderProfile onClick={this.onSenderProfileClick}
                     mxEvent={this.props.mxEvent}
@@ -971,8 +976,12 @@ export default class EventTile extends React.Component<IProps, IState> {
             onFocusChange={this.onActionBarFocusChange}
         /> : undefined;
 
-        const showTimestamp = this.props.mxEvent.getTs() &&
+        const showTimestamp = this.props.mxEvent.getTs()
-            (this.props.alwaysShowTimestamps || this.props.last || this.state.hover || this.state.actionBarFocused);
+            && (this.props.alwaysShowTimestamps
+            || this.props.last
+            || this.state.hover
+            || this.state.actionBarFocused);
+
         const timestamp = showTimestamp ?
             <MessageTimestamp showTwelveHour={this.props.isTwelveHour} ts={this.props.mxEvent.getTs()} /> : null;
 
@@ -1112,6 +1121,8 @@ export default class EventTile extends React.Component<IProps, IState> {
                     this.props.alwaysShowTimestamps || this.state.hover,
                 );
 
+                const isOwnEvent = this.props.mxEvent?.sender?.userId === MatrixClientPeg.get().getUserId();
+
                 // tab-index=-1 to allow it to be focusable but do not add tab stop for it, primarily for screen readers
                 return (
                     React.createElement(this.props.as || "li", {
@@ -1121,6 +1132,9 @@ export default class EventTile extends React.Component<IProps, IState> {
                         "aria-live": ariaLive,
                         "aria-atomic": "true",
                         "data-scroll-tokens": scrollToken,
+                        "data-layout": this.props.layout,
+                        "data-self": isOwnEvent,
+                        "data-has-reply": !!thread,
                         "onMouseEnter": () => this.setState({ hover: true }),
                         "onMouseLeave": () => this.setState({ hover: false }),
                     }, <>
@@ -1142,11 +1156,11 @@ export default class EventTile extends React.Component<IProps, IState> {
                                 onHeightChanged={this.props.onHeightChanged}
                             />
                             { keyRequestInfo }
-                            { reactionsRow }
                             { actionBar }
-                        </div>
+                        </div>,
-                        { msgOption }
+                        { reactionsRow },
-                        { avatar }
+                        { msgOption },
+                        { avatar },
                     </>)
                 );
             }

src/components/views/settings/tabs/user/AppearanceUserSettingsTab.tsx

@@ -37,6 +37,8 @@ import StyledRadioGroup from "../../../elements/StyledRadioGroup";
 import { SettingLevel } from "../../../../../settings/SettingLevel";
 import { UIFeature } from "../../../../../settings/UIFeature";
 import { Layout } from "../../../../../settings/Layout";
+import classNames from 'classnames';
+import StyledRadioButton from '../../../elements/StyledRadioButton';
 import { replaceableComponent } from "../../../../../utils/replaceableComponent";
 import { compare } from "../../../../../utils/strings";
 
@@ -241,6 +243,19 @@ export default class AppearanceUserSettingsTab extends React.Component<IProps, I
         this.setState({ customThemeUrl: e.target.value });
     };
 
+    private onLayoutChange = (e: React.ChangeEvent<HTMLInputElement>): void => {
+        let layout;
+        switch (e.target.value) {
+            case "irc": layout = Layout.IRC; break;
+            case "group": layout = Layout.Group; break;
+            case "bubble": layout = Layout.Bubble; break;
+        }
+
+        this.setState({ layout: layout });
+
+        SettingsStore.setValue("layout", null, SettingLevel.DEVICE, layout);
+    };
+
     private onIRCLayoutChange = (enabled: boolean) => {
         if (enabled) {
             this.setState({ layout: Layout.IRC });
@@ -373,6 +388,77 @@ export default class AppearanceUserSettingsTab extends React.Component<IProps, I
         </div>;
     }
 
+    private renderLayoutSection = () => {
+        return <div className="mx_SettingsTab_section mx_AppearanceUserSettingsTab_Layout">
+            <span className="mx_SettingsTab_subheading">{ _t("Message layout") }</span>
+
+            <div className="mx_AppearanceUserSettingsTab_Layout_RadioButtons">
+                <div className={classNames("mx_AppearanceUserSettingsTab_Layout_RadioButton", {
+                    mx_AppearanceUserSettingsTab_Layout_RadioButton_selected: this.state.layout == Layout.IRC,
+                })}>
+                    <EventTilePreview
+                        className="mx_AppearanceUserSettingsTab_Layout_RadioButton_preview"
+                        message={this.MESSAGE_PREVIEW_TEXT}
+                        layout={Layout.IRC}
+                        userId={this.state.userId}
+                        displayName={this.state.displayName}
+                        avatarUrl={this.state.avatarUrl}
+                    />
+                    <StyledRadioButton
+                        name="layout"
+                        value="irc"
+                        checked={this.state.layout == Layout.IRC}
+                        onChange={this.onLayoutChange}
+                    >
+                        { "IRC" }
+                    </StyledRadioButton>
+                </div>
+                <div className="mx_AppearanceUserSettingsTab_spacer" />
+                <div className={classNames("mx_AppearanceUserSettingsTab_Layout_RadioButton", {
+                    mx_AppearanceUserSettingsTab_Layout_RadioButton_selected: this.state.layout == Layout.Group,
+                })}>
+                    <EventTilePreview
+                        className="mx_AppearanceUserSettingsTab_Layout_RadioButton_preview"
+                        message={this.MESSAGE_PREVIEW_TEXT}
+                        layout={Layout.Group}
+                        userId={this.state.userId}
+                        displayName={this.state.displayName}
+                        avatarUrl={this.state.avatarUrl}
+                    />
+                    <StyledRadioButton
+                        name="layout"
+                        value="group"
+                        checked={this.state.layout == Layout.Group}
+                        onChange={this.onLayoutChange}
+                    >
+                        {_t("Modern")}
+                    </StyledRadioButton>
+                </div>
+                <div className="mx_AppearanceUserSettingsTab_spacer" />
+                <div className={classNames("mx_AppearanceUserSettingsTab_Layout_RadioButton", {
+                    mx_AppearanceUserSettingsTab_Layout_RadioButton_selected: this.state.layout == Layout.Bubble,
+                })}>
+                    <EventTilePreview
+                        className="mx_AppearanceUserSettingsTab_Layout_RadioButton_preview"
+                        message={this.MESSAGE_PREVIEW_TEXT}
+                        layout={Layout.Bubble}
+                        userId={this.state.userId}
+                        displayName={this.state.displayName}
+                        avatarUrl={this.state.avatarUrl}
+                    />
+                    <StyledRadioButton
+                        name="layout"
+                        value="bubble"
+                        checked={this.state.layout == Layout.Bubble}
+                        onChange={this.onLayoutChange}
+                    >
+                        {_t("Message bubbles")}
+                    </StyledRadioButton>
+                </div>
+            </div>
+        </div>;
+    };
+
     private renderAdvancedSection() {
         if (!SettingsStore.getValue(UIFeature.AdvancedSettings)) return null;
 
@@ -396,14 +482,17 @@ export default class AppearanceUserSettingsTab extends React.Component<IProps, I
                     name="useCompactLayout"
                     level={SettingLevel.DEVICE}
                     useCheckbox={true}
-                    disabled={this.state.layout == Layout.IRC}
+                    disabled={this.state.layout !== Layout.Group}
                 />
-                <StyledCheckbox
+
-                    checked={this.state.layout == Layout.IRC}
+                { !SettingsStore.getValue("feature_new_layout_switcher") ?
-                    onChange={(ev) => this.onIRCLayoutChange(ev.target.checked)}
+                    <StyledCheckbox
-                >
+                        checked={this.state.layout == Layout.IRC}
-                    { _t("Enable experimental, compact IRC style layout") }
+                        onChange={(ev) => this.onIRCLayoutChange(ev.target.checked)}
-                </StyledCheckbox>
+                    >
+                        { _t("Enable experimental, compact IRC style layout") }
+                    </StyledCheckbox> : null
+                }
 
                 <SettingsFlag
                     name="useSystemFont"
@@ -444,6 +533,7 @@ export default class AppearanceUserSettingsTab extends React.Component<IProps, I
                     { _t("Appearance Settings only affect this %(brand)s session.", { brand }) }
                 </div>
                 { this.renderThemeSection() }
+                { SettingsStore.getValue("feature_new_layout_switcher") ? this.renderLayoutSection() : null }
                 { this.renderFontSection() }
                 { this.renderAdvancedSection() }
             </div>

src/i18n/strings/en_EN.json

@@ -823,6 +823,7 @@
     "Offline encrypted messaging using dehydrated devices": "Offline encrypted messaging using dehydrated devices",
     "Enable advanced debugging for the room list": "Enable advanced debugging for the room list",
     "Show info about bridges in room settings": "Show info about bridges in room settings",
+    "New layout switcher (with message bubbles)": "New layout switcher (with message bubbles)",
     "Font size": "Font size",
     "Use custom size": "Use custom size",
     "Enable Emoji suggestions while typing": "Enable Emoji suggestions while typing",
@@ -1245,6 +1246,9 @@
     "Custom theme URL": "Custom theme URL",
     "Add theme": "Add theme",
     "Theme": "Theme",
+    "Message layout": "Message layout",
+    "Modern": "Modern",
+    "Message bubbles": "Message bubbles",
     "Set the name of a font installed on your system & %(brand)s will attempt to use it.": "Set the name of a font installed on your system & %(brand)s will attempt to use it.",
     "Enable experimental, compact IRC style layout": "Enable experimental, compact IRC style layout",
     "Customise your appearance": "Customise your appearance",

src/settings/Layout.ts

@@ -1,5 +1,6 @@
 /*
 Copyright 2021 Šimon Brandner <simon.bra.ag@gmail.com>
+Copyright 2021 Quirin Götz <codeworks@supercable.onl>
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
@@ -19,7 +20,8 @@ import PropTypes from 'prop-types';
 /* TODO: This should be later reworked into something more generic */
 export enum Layout {
     IRC = "irc",
-    Group = "group"
+    Group = "group",
+    Bubble = "bubble",
 }
 
 /* We need this because multiple components are still using JavaScript */

src/settings/Settings.tsx

@@ -41,6 +41,7 @@ import { Layout } from "./Layout";
 import ReducedMotionController from './controllers/ReducedMotionController';
 import IncompatibleController from "./controllers/IncompatibleController";
 import SdkConfig from "../SdkConfig";
+import NewLayoutSwitcherController from './controllers/NewLayoutSwitcherController';
 
 // These are just a bunch of helper arrays to avoid copy/pasting a bunch of times
 const LEVELS_ROOM_SETTINGS = [
@@ -321,6 +322,13 @@ export const SETTINGS: {[setting: string]: ISetting} = {
         displayName: _td("Show info about bridges in room settings"),
         default: false,
     },
+    "feature_new_layout_switcher": {
+        isFeature: true,
+        supportedLevels: LEVELS_FEATURE,
+        displayName: _td("New layout switcher (with message bubbles)"),
+        default: false,
+        controller: new NewLayoutSwitcherController(),
+    },
     "RoomList.backgroundImage": {
         supportedLevels: LEVELS_ACCOUNT_SETTINGS,
         default: null,

src/settings/controllers/NewLayoutSwitcherController.ts

@@ -0,0 +1,26 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import SettingController from "./SettingController";
+import { SettingLevel } from "../SettingLevel";
+import SettingsStore from "../SettingsStore";
+import { Layout } from "../Layout";
+
+export default class NewLayoutSwitcherController extends SettingController {
+    public onChange(level: SettingLevel, roomId: string, newValue: any) {
+        // On disabling switch back to Layout.Group if Layout.Bubble
+        if (!newValue && SettingsStore.getValue("layout") == Layout.Bubble) {
+            SettingsStore.setValue("layout", null, SettingLevel.DEVICE, Layout.Group);
+        }
+    }
+}