If you have the title of the new tab, you can create a new WWW::Mechanize::Chrome object and connect it to that new tab:

    my $chrome = $mech->driver;

    my @tabs = $chrome->getTargets()->get;

    # Assume that the first tab is the one we want:
    my $target_tab = $tabs[ 0 ];

    if( ! $target_tab->{targetId}) {
        die "This Chrome doesn't want more than one debugger connectio
+n";
    } else {
        $chrome->connect(tab => $target_tab)->get();
    };

    # Now, the WWW::Mechanize::Chrome object is mostly connected to th
+e new/other tab
[download]

Maybe you want to just create a separate, fresh object?

my $mech_tab = WWW::Mechanize::Chrome->new( tab => $new_tab_title );
[download]

Using multiple tabs or windows is a use case I haven't encountered that much, so there is very little existing support for it.

Thanks, your first example does the trick for me! (The second could be useful as well, depending on the use case.)

$mech->get('https://www.mscha.org/knmi/summer.cgi?month=-1');
$mech->follow_link(text=>'2020');    # opens a new window

my $chrome = $mech->driver;
my @tabs = $chrome->getTargets()->get;
my ($new_tab) = grep { $_->{url} =~ m{graph} } @tabs;
$chrome->connect(tab=>$new_tab)->get;

my $png = $mech->content_as_png;
[download]

I don't have control over the site I want to eventually use this for, and it opens new tabs all over the place. So I do need to be able to do this.
It might be useful for other people to include some documentation or an example that shows tab switching.

> https://metacpan.org/pod/WWW::Mechanize::Chrome#$mech-%3Etab

Yes, I read the documentation. But I don't see how that helps me.

>Access the tab hash of the Chrome::DevToolsProtocol::Target instance.

Never used this before, but I am going to guess that this means $tag is a hash reference that contains all the opened tabs. Maybe explore the contents of $tag in the example.

Why not?