In the last two years we updated jmdns
(which is being used to discover network boards) to address security and performance problems in the older versions. The boards are now added/removed based on the information coming from that library, so if a board disappears it is due to mdns reporting the "disconnection". #8408
Description
Below problem solved. Updating Python from 2.7.13 to 3.7.2 fixed the ports disappearing problem. Adding a delay(300); after web page html code but before client.stop() fixed the slow web page display in desktop Chrome on XP and Windows 10. Android Chrome was always fast.
I have used Arduino IDE 1.6.11 on a wired desktop running XP SP2 to wirelessly program 4 Nodemcu devices without any problem for over a year.
I got a new laptop with Windows 10 and installed 1.6.11 and all the network ports show up and work immediately but then disappear and the port is greyed out in a minute or so.
I can only upload once or twice before the port is gone.
If I restart the laptop the ports show up and work again for a short time. Nothing I have tried has worked so far including allowing port 8266 or turning off the firewall.
Also compiling is very slow now.