Front end does not properly reconnect after waking machine from sleep

[tsmaeder]

Bug Description:

I was travelling and working on Theia. I closed my laptop exiting the train and opened it again at home (in my home network). Now the UI seems disconnected from the back-end:

• Code assist in a typescript file is not available (shows "loading...").
• When I edit a file and press "save", the file remains dirty

In the log, I have two messages:

Failed to load resource: net::ERR_NETWORK_IO_SUSPENDED localhost:51936/socket.io/?EIO=4&transport=polling&t=gvqutf8x:1         
Failed to load resource: net::ERR_NETWORK_IO_SUSPENDED http://localhost:51936/socket.io/?EIO=4&transport=polling&t=gvs2sm1n

Steps to Reproduce:

n/a

Additional Information

• Operating System: Windows 11
• Theia Version: 1.57.100

[tsmaeder]

We used to have this problem in the past, but it was fixed for a while: #12707

[tsmaeder]

@msujew what seems odd to me is the "transport=polling" in the erroring URI's.

[msujew]

@tsmaeder I would assume that after the initial disconnect, the frontend will attempt to reconnect using the polling mechanism first before attempting to switch to the websocket connect.