Works flawlessly on my W10 machine.

It did not work for me (Windows 10 Home).

Commands aren't clear... ‘CALL:PowrProf.dll SetSuspendState 0 1 0’, ...
Tip : do not copy the quote marks nor the ending comma.

I get this error after countdouwn :
If you still get this page even when the "Check Button" reports successful connection, it means the application cannot be accessed (path is not correct in the options page). If the path to the executable is correct and the native client is connected, you can debug the connection by enabling console logs.

Fix this error pls

I'd like if it could work with Wetransfer uploads too

I want to close a firefox window or tab with timer.
I olready can adjust timer for system (with terminal in linux as -command:shutdown xx:xx- )
How can I find like that add-on.

Commands aren't clear... ‘CALL:PowrProf.dll SetSuspendState 0 1 0’, ...
Tip : do not copy the quote marks nor the ending comma.

I get this error after countdouwn :
If you still get this page even when the "Check Button" reports successful connection, it means the application cannot be accessed (path is not correct in the options page). If the path to the executable is correct and the native client is connected, you can debug the connection by enabling console logs.

Native client 0.6.6 is installed, however I'm not seeing any sort of path to edit on the options page.
Tutorial page is for chrome, video tutorial is for chrome...

What should we look for into logs ?

Please fix this. (W7x64 - FF57.0.2)

It didn't work for me. only count down that count to 0 but no action! some years ago I had an add-on with the name and icon similar to the name and icon of this add-on but that years it was functional.

Great extension given the workarounds that are needed to make this work as webextension (which is needed for FF 57+).

However, the "check connection page" which you get pressing Open on settings page might be misleading, if it claims that " If you still get this page even when the "Check Button" reports successful connection, it means the application cannot be accessed (path is not correct in the options page)", since Auto Shutdown might still work.

Set shutdown /s /f /t 120 (on windows) to have two minutes to cancel the shutdown with shutdown /a in a command window.

Hint: Author replies fast on https://github.com/andy-portmen/auto-shutdown/issues

a usefull addon for me, works perfect on win 10

It's not a straightforward installation, as well as the extension, other software has to be downloaded and installed.

Seems to run ok, and the clock countdown to zero, but then an error is indicated. The error suggests a path error but there is no path available to edit.

Altogether a messy extension.

Contacted the author for help.

Edit 30/9/17
No response from author - says a lot when the author doesn't respond to bug reports on his own support site.

Pretty safe to assume this extension is dead.

Restart didn't work, I tried many times. OS: Win 10 Pro 64-bit with Firefox 53.0.3.

It's a little bit complicated when you want to shutdown. I don't understand why you must download native-client 0.3.8 or windows.zip (install.bat).