Plotting fails in Big Sur for some - both x86_64 and M1 [BUG]

Describe the bug Plotting fails in Big Sur - both x86_64 and M1 for some but not everyone.

To Reproduce Install on Big Sur. It may require not having dev tools installed to replicate though it will replicate on Big Sur on M1 with devtools installed.

On x86_64 plotting “starts” but if you open the plot log all you see is one entry “Loading…”. On Big Sur it doesn’t even pop the creating plots page.

This came in in RC3 with the switch to Click and the RC4 fix didn’t fix this.

debug.log from M1:

12:07:37.540 daemon __main__                   : ERROR    Error while handling message: Traceback (most recent call last):
  File "/Users/hoffmang/chia-blockchain/chia-blockchain-gui/../src/daemon/server.py", line 217, in safe_handle
    response, sockets_to_use = await self.handle_message(websocket, decoded)
  File "/Users/hoffmang/chia-blockchain/chia-blockchain-gui/../src/daemon/server.py", line 322, in handle_message
    response = await self.start_plotting(cast(Dict[str, Any], data))
  File "/Users/hoffmang/chia-blockchain/chia-blockchain-gui/../src/daemon/server.py", line 551, in start_plotting
    "command_args": self._build_plotting_command_args(request, True),
  File "/Users/hoffmang/chia-blockchain/chia-blockchain-gui/../src/daemon/server.py", line 439, in _build_plotting_command_args
    a = request["a"]
KeyError: 'a'

debug.log from x86_64

18:31:01.565 daemon __main__                   : ERROR    Error while handling message: Traceback (most recent call last):
  File "src/daemon/server.py", line 217, in safe_handle
  File "src/daemon/server.py", line 322, in handle_message
  File "src/daemon/server.py", line 551, in start_plotting
  File "src/daemon/server.py", line 439, in _build_plotting_command_args
KeyError: 'a'

[hoffmang9]

Thanks to both @arvidn and @wjblanke for the painful find and fix!

[mariano54]

I also experienced a plotting issue on Mac OS Catalina 10.15.7, on a machine that was not M1.