Both ICEpush JavaScript consoles captured below. Since both windows appear to be attempting a connection to the server, it appears that they are not successfully electing a master window:
[icepush.9ade1] : picked up notifications for this window: v499jla7
[icepush.9ade1.async-connection] : failed to connect, first retry...
[icepush.9ade1] : connection in trouble
[icepush.9ade1.async-connection] : closing previous connection...
[icepush.9ade1.async-connection] : connect...
[icepush.9ade1] : received notifications: v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5
[icepush.9ade1.async-connection] : closing previous connection...
[icepush.9ade1.async-connection] : connect...
[icepush.9ade1] : picked up notifications for this window: v499jla7
[icepush.9ade1.async-connection] : blocking connection stopped at server's request...
[icepush.9ade1] : picked up notifications for this window: v499jla7
[icepush.9ade1.async-connection] : failed to connect, first retry...
[icepush.9ade1] : connection in trouble
[icepush.9ade1.async-connection] : closing previous connection...
[icepush.9ade1.async-connection] : connect...
[icepush.9ade1] : received notifications: v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5
[icepush.9ade1.async-connection] : closing previous connection...
[icepush.9ade1.async-connection] : connect...
[icepush.9ade1] : picked up notifications for this window: v499jla7
[icepush.9ade1.async-connection] : blocking connection stopped at server's request...
[icepush.9ade1] : picked up notifications for this window: v499jla7
[icepush.7e972] : picked up notifications for this window: v7k454d5,v499jla7
[icepush.7e972.async-connection] : failed to connect, first retry...
[icepush.7e972] : connection in trouble
[icepush.7e972.async-connection] : closing previous connection...
[icepush.7e972.async-connection] : connect...
[icepush.7e972] : received notifications: v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5
[icepush.7e972.async-connection] : closing previous connection...
[icepush.7e972.async-connection] : connect...
[icepush.7e972] : picked up notifications for this window: v7k454d5,v499jla7
[icepush.7e972] : picked up notifications for this window: v7k454d5,v499jla7
[icepush.7e972.async-connection] : failed to connect, first retry...
[icepush.7e972] : connection in trouble
[icepush.7e972.async-connection] : closing previous connection...
[icepush.7e972.async-connection] : connect...
[icepush.7e972] : received notifications: v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5
[icepush.7e972.async-connection] : closing previous connection...
[icepush.7e972.async-connection] : connect...
[icepush.7e972] : picked up notifications for this window: v7k454d5,v499jla7
[icepush.7e972.async-connection] : failed to connect, first retry...
[icepush.7e972] : connection in trouble
[icepush.7e972.async-connection] : closing previous connection...
[icepush.7e972.async-connection] : connect...
[icepush.7e972] : picked up notifications for this window: v7k454d5,v499jla7
[icepush.7e972] : received notifications: v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5,v499jla7,v7k454d5
[icepush.7e972.async-connection] : closing previous connection...
[icepush.7e972.async-connection] : connect...
[icepush.7e972] : picked up notifications for this window: v7k454d5,v499jla7
Basically the issue can be described as follows:
if a tab was the owner of the blocking connection once, but lost it eventually to another tab, its timeout bomb wasn't getting stopped causing superfluous blocking requests to be send by the losing tab.
Now if a JavaScript Bridge instance detects it's not the owner of the blocking connection it will stop its timeout bomb. Marking this one as FIXED.