I always tell people that 'nothing can go wrong' and that 'their computer won't even remember' if I boot their systems from my Ubuntu-installed pendrive, but I recently found out that this is not true. Booting from a pendrive has the possibility of changing the hardware clock of the computer it is used on.
As explained e.g. in these help pages, Linux and Windows interpret the hardware clock as UTC and local time, respectively. This means that in a dual-boot system, one wants to make Linux read the system clock as local time too, to prevent a mismatch in Windows. The problem is that I want to use my pendrive both in computers with Linux as their main OS and computers with Windows as their main OS, so whatever decision I make for my pendrive (local time vs UTC), it's not going to fit all computers.
Is there a way to simply prevent Ubuntu from changing the system clock, so at least I don't mess up other people's setups? If that means the pendrive system sometimes does not display the correct time, then so be it.
NOTE TO EAGER FLAGGERS: I know that this question has been asked a thousand times on this site by dual-booters (see the two Q&A's below), but for as far as I could find the proposed solution was always to adjust Linux settings to interpret the hardware clock as local time (or make Windows interpret it as UTC). This is not an option for me since I want a portable system that does not change any clocks.