if M5Image.set_network_img_src() call receives any kind of error it will hang the UI completely even if try..except is used. Setting image source, label text etc. will no longer work but all other code will continue to run in the background like timers or main loop.

example:

try:
  print("before")
  image0.set_network_img_src('http://192.168.1.100/someimage.png')
  print("after")
except:
  print("except")

will print 2 first but never the third "except print" when any kind of error happens (loading error comes delayed):

before
after
lodepng_error: invalid ADLER32 encountered (checking ADLER32 can be disabled)

You can test it by taking any .png and open it with a notepad and mess the contents to corrupt it. Then download it with set_network_img_src