My Flowdock UserStyle. Goes in ~/Library/Application Support/Flowdock/userstyle.css

userstyle.css

.emojie {
  line-height: 1rem !important;
}

.bubble.thread {
  opacity: 0.65;
}

.bubble.green {
  border-color: #9554D2 !important;
  color: #9554D2 !important;
  fill: #9554D2 !important;
}

.bubble.dirty-green {
  border-color: #00B19E !important;
  color: #00B19E !important;
  fill: #00B19E !important;
}

.bubble.red {
  border-color: #FF5050 !important;
  color: #FF5050 !important;
  fill: #FF5050 !important;
}

.bubble.blue {
  border-color: #FF70D2 !important;
  color: #FF70D2 !important;
  fill: #FF70D2 !important;
}

.bubble.yellow {
  border-color: #89D011 !important;
  color: #89D011 !important;
  fill: #89D011 !important;
}

.bubble.purple {
  border-color: #FAD300 !important;
  color: #FAD300 !important;
  fill: #FAD300 !important;
}

.bubble.orange {
  border-color: #FFA273 !important;
  color: #FFA273 !important;
  fill: #FFA273 !important;
}

.bubble.teal {
  border-color: #5493E3 !important;
  color: #5493E3 !important;
  fill: #5493E3 !important;
}

.bubble.brown {
  border-color: #BDE3FF !important;
  color: #BDE3FF !important;
  fill: #BDE3FF !important;
}

.bubble.pink {
  border-color: #ADA7A7 !important;
  color: #ADA7A7 !important;
  fill: #ADA7A7 !important;
}

.tab-list-shadow .fa-chevron-up {
  color: rgba(255, 255, 255, 0.6) !important;
  padding: 0 50px;
  background-color: rgba(151, 0, 0, 0.6) !important;
}

.tab-list-shadow .fa-chevron-down {
  color: rgba(255, 255, 255, 0.6) !important;
  padding: 0 50px;
  background-color: rgba(151, 0, 0, 0.6) !important;
}

.tab-link {
  padding-top: 0.5rem !important;
  padding-bottom: 0.5rem !important;
}

/* Warn users away from accidentally making new threads */
.chat-panel .message-input::-webkit-input-placeholder {
  color: #CC2929 !important;
}