It still isn´t reliable with suspending. If it fails after unsuspending it does so immediately, but often times it just doesn´t fail. I´ll try having the window in focus and see if it also fails without suspending.
Here´s the file I´m testing with, it basically just sends an AJAX request every second until it fails.
wackytoaster.at/parachute/ajaxtimer.c3p
EDIT: First test it failed after only 136 seconds even with the window permanently in focus.
EDIT2: The second test is now at 29 minutes and still going... :V
I decided to end the test after almost 40 minutes and suspended the window for 5 minutes. Guess what, it STILL didn´t fail? What the hell? I´ve now suspended and unsuspended several times and it´s still going. I think it´s safe to say this one just won´t fail no matter what.