I recently replaced a W10 remote that died. Previously, the power button would turn on both the TV and the computer. The new remote only seems to do one or the other. Is there something I need to do to enable this or has the behaviour changed? (My previous remote was purchased April 2019.)
Yes, because some users just want either one of these devices to wake up instead of both. (sometimes people just want to watch the TV without waking up the PC) You can still do that by learning the power on/off key from your TV remote, of course, you would need to wake them up separately.