Unfortunately, event.metaKey does not evaluate to true on Windows when the ctrl key is held on click.

Fortunately, event.ctrlKey does evaluate to true in these situations. Also, you may want to consider shift + clicks in your event handler.

Thus, your cross platform jquery flavored javascript code would look something like:

$('ul#tabs li a').on('click', function(e) {
    var link = $(this).attr('href');

    // Check "open in new window/tab" key modifiers
    if (e.shiftKey || e.ctrlKey || e.metaKey) {
      window.open(link, '_blank');
    } else {
      $('#content').fadeOut('fast',function(){
        window.location = link;
      });
    }
  }
});

Shift/click selects contiguous items, Cmd/click discontiguous.
You can combine the two to make large & small selections. I don't have a screen recorder that can show keys held whilst I do this to show you, but as an example…

If you start with a list of files in a folder; click the first, shift-click the third, then Cmd/click the fifth & finally Shift/click the seventh.
You will then have 1, 2, 3, 5, 6, 7 selected, with 4 missed out.

You can also use Cmd/click to deselect - so the above end result could also be obtained by clicking 1, Shift/clicking 7, then de-selecting 4 using Cmd/click.

In HTML files the command is "Open Link" (editor.action.openLink). This command does not have, by default, associated a key combination. You can assign one by using the Preferences -> Keyboard Shortcuts command from the menu (click on the gear on the bottom of the primary side bar).

In other contexts (source code in various programming languages), the combination Ctrl+click (or Cmd+click on macOS) when the cursor is on an identifier (constant name, variable name, function name, class name, etc.) is equivalent with command "Go to Definition" (editor.action.revealDefinition). This command has, by default, associated the key F12.

In Tools > Options > Edit, uncheck the box for "Use Ctrl+Click to follow hyperlink".

First and foremost, please note that in VS Code for macOS, the familiar Ctrl + click from Windows / Linux operating systems has been replaced with ⌘ + click (i.e.: "command + click"). Try that first before proceeding any further as that shortcut should work out of the box without any special modifications.

However, if the above still doesn't work for you then try fixing the problem by editing your settings.json file. To do that, press F1, type settings json, then click Open Settings (JSON), and then do one of the following:

To use ⌘ + click as your "Go to definition" shortcut, ensure the following line exists in your JSON settings:

"editor.multiCursorModifier": "alt",

What this does is it explicitly sets VS Code's "add another cursor" shortcut to option + click (try it out for yourself!), thus freeing up ⌘ + click to be used for the "Go to definition" operation.

Conversely, to use option + click as your "Go to definition" shortcut instead, add:

"editor.multiCursorModifier": "ctrlCmd",

Note: the above line will actually set the "add another cursor" shortcut to ⌘ + click (not Ctrl + ⌘ + click, as implied by the JSON value).