Is this a recent improvement? I'm pretty sure I had Runelite back when I came up with the AHK script, two or three years ago. Or maybe the issue came up while I was playing RS3? It's been a while so I don't remember the details!

Nope, but you do have to enable it in the settings last I checked. Not certain about RS3.

Ah I see, good to know! Thank you for that. I searched the web and apparently it's part of the "Login Screen" plugin https://runelite.net/blog/show/2018-11-22-1.5.1-Release/