[NooneAtAll3]

no

considering free windows being light theme only, it should be a button, not a "system default"

[zamadatix]

By "free windows" do you just mean an unactivated copy of Windows? That doesn't prevent the user from configuring their preference in the browser itself.

[xnorswap]

There should be a button too, but it's simple to add a line so that it also defaults to any provided preference.

[CamperBob2]

That's fine, too. Either way, give the user the choice.

[gdcbe]

… is that even legal to do for microsoft? Are there no requirements to adhere to certain standards? Would have thought that is part of it.

[love2read]

what would the requirement be? "thou must provide the full paid service to those who do not pay"?