Andrey, so I believe the issue is the fact the server has to load the application into memory off disk that first time, and given you appear to be using Ajax client, there is a 60 second socket timeout that is likely causing the disconnect etc. It also explains why when you go back on a new tab it does open, as the application is in memory at that point, so the server just has to connect your session...
I believe the following Article should be of help:
Look under IIS and the 'SocketTimeOutInSeconds' setting, set that to a value large enough to cover the time it takes the QVS to get that app loaded into memory. You can more likely use the Desktop Client to get that value, be sure to add a buffer on top of that! 🙂 Hopefully that does the trick for you. Oh, in the IIS manager, the name of the setting is as above and the value would be the number of seconds you want.
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