Have two different URLs show the homepage

Question

I want to have two different URLs for the same page. In particular I want to have a specific URL that shows my frontpage. The URL should be kept however. So these two URLs

www.mywebsite.com/
www.mywebsite.com/page1

should both be displaying the frontpage. I thought this could be done with WordPress's add_rewrite_rule function, but I didn't have success with that yet.

When I do this

add_rewrite_rule('^page1', 'index.php', 'top');

It acts more like a redirect. When I try to access www.mywebsite.com/page1 I get redirected to my homepage. But I want the URL to stay the same, which this doesn't seem to do.

When I do this

add_rewrite_rule('^page1', 'index.php?pagename=$matches[1]', 'top');

it just shows the page www.mywebsite.com/page1 instead of the homepage.

I fumbled around with the rewrite rules for hours now and I'm pretty much at my wits end. Is what I want even possible?

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Edit: This is different from many other questions in that I am trying to show the frontpage. The solution provided here solves this, when you can use the locations query var, but I didn't get it to work with that.

Answer 1

WordPress will always try to redirect to the canonical URL to prevent duplicate content, so you'll have to disable that mechanism to get another URL to display that page.

First, your rewrite rule:

add_rewrite_rule('^page1', 'index.php?pagename=your-page-name', 'top');

Then filter redirect_canonical to return false if the requested URL is your 2nd home URL:

function my_redir_check( $redirect_url, $requested_url ){
    if( home_url( '/page1/' ) == trailingslashit( $requested_url ) ){
        return false;
    }
    return $redirect_url;
}
add_filter( 'redirect_canonical', 'my_redir_check', 10, 2 );