Hi,

I checked on your site and add custom css to Customize > Addtional CSS to fix this issue ( http://prntscr.com/m6xxv7 )

.site-main #buddypress button.wp-switch-editor, .site-main #buddypress button#insert-media-button {
    float: left;
    box-sizing: content-box;
    position: relative;
    top: 1px;
    background: #ebebeb;
    color: #666;
    cursor: pointer;
    font-size: 13px;
    line-height: 19px;
    height: 20px;
    margin: 5px 0 0 5px;
    padding: 3px 8px 4px;
    border: 1px solid #e5e5e5;
}
.site-main #buddypress .mce-toolbar .mce-btn button {
    padding: 2px 3px;
    line-height: normal;
    color: #595959;
    background: transparent;
    border: 0;
    text-transform: none;
    font-size: 13px;
}

Please check it again.

Best Regards,

PenciDesign