I'm getting this in Chrome 66.0.3359.117 on Linux:
Uncaught (in promise) r {code: "HARMONY_OPERATION_FORBIDDEN", message: "Skipping not allowed.", status: -1, debug: {…}}
Promise.then (async)
f.playURI @ web-player.4bd688a3.js:1
T @ web-player.4bd688a3.js:1
(anonymous) @ web-player.4bd688a3.js:1
(anonymous) @ web-player.4bd688a3.js:1
value @ web-player.4bd688a3.js:1
value @ web-player.4bd688a3.js:1
(anonymous) @ web-player.4bd688a3.js:1
invokeGuardedCallback @ web-player.4bd688a3.js:1
invokeGuardedCallbackAndCatchFirstError @ web-player.4bd688a3.js:1
I @ web-player.4bd688a3.js:1
k @ web-player.4bd688a3.js:1
N @ web-player.4bd688a3.js:1
w @ web-player.4bd688a3.js:1
M @ web-player.4bd688a3.js:1
x @ web-player.4bd688a3.js:1
_n @ web-player.4bd688a3.js:1
batchedUpdates @ web-player.4bd688a3.js:1
Be @ web-player.4bd688a3.js:1
gn @ web-player.4bd688a3.js:1
interactiveUpdates @ web-player.4bd688a3.js:1
bn @ web-player.4bd688a3.js:1
d @ raven.js:386

Tried in Firefox but the web UI crashes there before I can even try to click on a song...