Slack image and video hide userscript

userscript.css

.sgh-flyout {
        position: absolute;
        top: 0;
        left: 0;
        z-index: 9999;
}
 
.sgh-icons {
        position: relative;
        float: left;
        right: 0;
        margin-left: -100%;
        -webkit-transition: margin-left .25s;
        padding: .5em 0;
        background: #e5e5e5;
        border: 1px solid #ddd;
        border-radius: 0 0 4px 0;
}
 
.sgh-icons:hover {
        margin-left: 0;
}
 
.sgh-hide {
        float: left;
        clear: both;
        white-space: nowrap;
        color: #999;
        padding: 0 .75em 0 .5em;
        margin-bottom: .5em;
}
 
.sgh-hide:hover {
        color: #2d2d2d;
}
 
.sgh-icon {
        padding-right: .5em;
}
 
.sgh-flyout a:hover .sgh-icon {
        text-decoration: none;
}
 
.sgh-hit {
        position: absolute;
        top: 0;
        right: -1.5em;
        width: 1.5em;
        height: 7em;
}
 
.sgh-tab {
        position: absolute;
        top: .75em;
        left: 0;
        width: .5em;
        -webkit-transition: width .25s;
        height: 2em;
        background: #e5e5e5;
        border: 1px solid #ddd;
        border-radius: 0 4px 4px 0;
}
 
.sgh-icons:hover .sgh-tab {
        width: 0;
        border: none;
}

userscript.js

sgh = {};
 
sgh.InitSlackGifHide = function(){
        // trigger message collapse when image is clicked
        $("#messages_container").delegate('.msg_inline_img','click',function(e) {
        e.preventDefault();
        e.stopPropagation();
        $(e.target).closest('.message').find('.msg_inline_img_collapser').trigger('click');
    });
}
 
sgh.SetFlyoutEvents = function () {
        // hide all items of category clicked in flyout
        $(".sgh-hide").on('click',function(e) {
        e.preventDefault();
 
        var closeMessage = null;
 
        switch($(e.target).data("hide")) {
                case "images":
                        closeMessage = $('.msg_inline_img').closest('.message');
                        break;
                case "video":
                        closeMessage = $('.msg_inline_video').closest('.message');
                        break;
                case "all":
                        closeMessage = $('.message');
                        break;
        }
 
        closeMessage.find('.fa-caret-down').trigger('click');
 
    });
 
}
$(function(){
  $("body").append('<div class="sgh-flyout"><div class="sgh-icons"><div class="sgh-hit"><span class="sgh-tab"></span></div><a href="#hide" data-hide="images" class="sgh-hide"><i class="sgh-icon icon-collapse-alt"></i>Images</a><a href="#hide" data-hide="video" class="sgh-hide"><i class="sgh-icon icon-collapse-alt"></i>Videos</a><a href="#hide" data-hide="all" class="sgh-hide"><i class="sgh-icon icon-collapse-alt"></i>All</a></div></div>');
  sgh.InitSlackGifHide();
  sgh.SetFlyoutEvents();
});

Just like https://gist.github.com/wernull/7330137 but for Slack.com