diff --git a/Dockerfile b/Dockerfile
index db32b135..6faeffe5 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -13,7 +13,7 @@ RUN bundle install --jobs 4
 
 RUN curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | apt-key add -
 RUN echo "deb https://dl.yarnpkg.com/debian/ stable main" | tee /etc/apt/sources.list.d/yarn.list
-RUN apt-get update && apt-get install -y yarn
+RUN apt-get update && apt-get install -y yarn netcat
 
 RUN mkdir /app/log
 
diff --git a/config/initializers/sanitizer.rb b/config/initializers/sanitizer.rb
index 46ca6ebd..7f6a5e32 100644
--- a/config/initializers/sanitizer.rb
+++ b/config/initializers/sanitizer.rb
@@ -7,4 +7,4 @@ safe_list =
     Loofah::HTML5::WhiteList
   end
 
-safe_list::ALLOWED_PROTOCOLS.merge(%w(message onenote))
+safe_list::ALLOWED_PROTOCOLS.merge(%w(message onenote obsidian))
diff --git a/script/poll-for-db b/script/poll-for-db
index f6877f34..05b1db4b 100755
--- a/script/poll-for-db
+++ b/script/poll-for-db
@@ -1,10 +1,12 @@
 #!/bin/bash
 
+echo "==> Polling DB…"
+
 appdir=$(cd $(dirname "$0")/.. && pwd)
 [ -f /etc/app-env ] || exec "$appdir/script/docker-environment" $0 $@
 
 for i in {1..60}; do
-  curl -sf telnet://db:3306 >/dev/null && exit
+  nc -z -w5 db 3306 && exit
   sleep 1
 done