Disable other generation buttons while process is running

[sedetweiler]

Messed myself up today as I forgot I was doing an enlargement on one tab and came back to the PC and started to play with other prompts. I supposed there are different ways to do this, from a status bar with running job info or just disabling the buttons that can break things. Not a high priority.

[lggcpp]

收到！谢谢合作