jitsi_app_c0/css/filmstrip/_horizontal_filmstrip.scss

%align-right {
    @include flex();
    flex-direction: row-reverse;
    flex-wrap: nowrap;
    justify-content: flex-start;
}

.horizontal-filmstrip .filmstrip {
    position: absolute;
    bottom: 0;
    right: 0;
    padding: 10px 5px;
    @extend %align-right;
    transition: bottom .3s;
    z-index: $filmstripVideosZ;
    box-sizing: border-box;
    width: 100%;
    position: fixed;

    /*
     * Firefox sets flex items to min-height: auto and min-width: auto,
     * preventing flex children from shrinking like they do on other browsers.
     * Setting min-height and min-width 0 is a workaround for the issue so
     * Firefox behaves like other browsers.
     * https://bugzilla.mozilla.org/show_bug.cgi?id=1043520
     */
     @mixin minHWAutoFix() {
        min-height: 0;
        min-width: 0;
    }

    &.reduce-height {
        bottom: calc(#{$newToolbarSizeWithPadding} + #{$scrollHeight});
    }

    &__videos {
        @extend %align-right;
        position:relative;
        padding: 0;
        /* The filmstrip should not be covered by the left toolbar. */
        bottom: 0;
        width:auto;
        overflow: visible !important;

        &#remoteVideos {
            border: $thumbnailsBorder solid transparent;
            transition: bottom 2s;
            flex-grow: 1;
            @include minHWAutoFix()
        }

        /**
         * The local video identifier.
         */
        &#filmstripLocalVideo {
            align-self: flex-end;
            display: block;
            margin-bottom: 8px;
        }

        &.hidden {
            bottom: calc(-196px - #{$newToolbarSizeWithPadding});
        }

        .remote-videos-container {
            display: flex;
        }
    }

    .remote-videos-container {
        transition: opacity 1s;
    }

    &.hide-videos {
        .remote-videos-container {
            opacity: 0;
            pointer-events: none;
        }
    }

    #filmstripRemoteVideos {
        @include minHWAutoFix();

        display: flex;
        flex: 1;
        width: auto;
        justify-content: flex-end;
        flex-direction: row;

        #filmstripRemoteVideosContainer {
            flex-direction: row-reverse;
            /**
             * Add padding as a hack for Firefox not to show scrollbars when
             * unnecessary.
             */
            padding: 1px 0;
            overflow-y: hidden;
            overflow-x: scroll;
        }
    }

    .videocontainer {
        margin-bottom: 10px;
    }
}


/**
 * Workarounds for Edge and Firefox not handling scrolling properly with
 * flex-direction: row-reverse.
 */
 @mixin undoRowReverseVideos() {
    .horizontal-filmstrip {
        #remoteVideos #filmstripRemoteVideos #filmstripRemoteVideosContainer {
            flex-direction: row;
        }
    }
}

/** Firefox detection hack **/
@-moz-document url-prefix() {
    @include undoRowReverseVideos();
}

/** Edge detection hack **/
@supports (-ms-ime-align:auto) {
    @include undoRowReverseVideos();
}