> on windows, the most common way to open a link in a new tab is with a middle-click.
 
I know, and I was tempted to add that; however this is a very specific case only for windows, where the accel + click is cross-platform, and the bug was specifically for that one.
It's not also sure if we decided to land this fix: this is a sort of "workaround"; we simulate something in a way that is definitely not the native, but we just mock it. I prefer avoid adding code to simulate anything else if it's not required.

> context-menu -> open in new window, is also very common (even on osx). 
Panels doesn't have context menu.

> and then what about links with `target=_blank`?

Not sure what you mean. They will be opened in a new tab too; when this combo is made the `target` is ignored – I mean, on regular window. I mimic that behavior.

> it feels like there should be (or maybe there already is?) an event in the platform that generally corresponds with "open link in new tab", however it gets triggered.

Again, not sure what you mean. We open a link in a new tab and the tab's events are emitted consequentially.