Regardless of the autosave setting, Pancake will do an emergency save whenever Grasshopper loses responsiveness for too long. Remember the time when you wired a buggy connection to make Grasshopper hang forever and didn't save your file? That is past.
How to enable/disable this feature?
Navigate to "Pancake" menu, check/uncheck "Enable Hang Protection".
This feature is disabled by default.
Safe mode will suppress this feature temporarily.
Where to find the emergency save?
They are usually stored in the same location of the original document, with a label "_PancakeEmergency".
If you haven't saved, or the former location is unwritable, or the previous save failed, the emergency save will be put in the temporary directory (press Windows+R, input %temp% and click OK), starting with "PancakeEmergency_".
How long does Pancake wait before saving?
The threshold of Pancake recognizing Grasshopper has lost responsiveness is 60-90 seconds (as of 18.104.22.168), or 60-62 seconds in older versions.
If the system load is extremely high, you may need to wait significantly longer.
What will be saved?
Pancake will only save the current Grasshopper document, excluding any other loaded scripts nor the Rhino file.
Alongside the saved file, Pancake will create a text file, describing what leads to the problem. For example, you will read messages like Problem might be caused by Component_PipeSurface in SurfaceComponents, attached with a stacktrace.
As of 22.214.171.124, Pancake will save your document correctly when the editor is inside a cluster. Before this version, Pancake will save the cluster instead.
What else should I also notice?
Remember to lock the solver before you load the emergency save, because the file is likely to raise another hang.
Hang is not always a bad thing. If you are running a time-consuming task, switching off Hang Protection will improve the performance.
This feature applies to hang only. Pancake is powerless to crash. We recommend you to leave AutoSave feature on.
As of now, Pancake cannot detect hang during plugin initilization, that is, between the time when Grasshopper is launched and the editor window pops up.
For technical nerds...
Double-click the Grasshopper canvas and input #pcRoutineStatus to see the internal status of HangDetector.