Remove unnecessary route delay for Windows 7 and newer.

[bernerdad]

This PR considers removing a 5 second delay on Windows when setting up the tunnel. We have been using this change for 3+ years in the Windscribe desktop app on Windows 10/11, with no adverse impact.

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[schwabe]

Could you please explain how you come to the conclusion that this is no longer necessary and how you tested that?

[schwabe]

we don't support anything older than Vista anymore and probably not even Vista at this point. So you really would need to remove the whole block instead, instead of basically making is dead code.

[bernerdad]

I wasn't aware Win7 was the minimum supported OS now. I have removed the dead code. With respect to concluding this code is no longer necessary; our Windscribe desktop application has been running with this change in production since late 2021, with ~25000 daily active OpenVPN connections. Prior to making this change, we observed a substantial delay when initializing the tunnel on Windows. Removing this 5s delay, and another one that has already been fixed by OpenVPN, resolved this delay.

[schwabe]

Yes. But your windscribe tunnel is only one very specific tunnel configuration. So you basically have only tested it in one very specific configuration that removing the delay works. Without really knowing what the specific problem was that this delay address, it is a hard to judge it if it is safe to remove nowadays.

Also if such a behavioural change is itroduced, it should be mentioned in the Changes.rst

[cron2]

Yes. But your windscribe tunnel is only one very specific tunnel configuration. So you basically have only tested it in one very specific configuration that removing the delay works. Without really knowing what the specific problem was that this delay address, it is a hard to judge it if it is safe to remove nowadays.

The overall point is somewhat moot, as this is in a code path that nobody really gets to use anymore in new OpenVPN installs - it's using TAP+DHCP, while really everything should use win-dco and ipapi (via iservice) these days... which does not suffer from automatic route-delay settings for DHCP.

Removing code paths that made sense on long-forgotten Windows parts is actually a good thing :-) - having a bit more testing would be good, though.

Also if such a behavioural change is itroduced, it should be mentioned in the Changes.rst

Indeed. But since half the regular contributors send stuff without Changes.rst updates these days, it's not something that would hold up the patch if acceptable otherwise.