Remove Query String from URL on Redirect - Redirection Plugin

I've solved it by slight change in plugin code, by adding two filter hooks. Hoping that author will incorporate those hooks - 2 non-destructive lines, as they allows us much more customization of plugin behaviour. Explained here in detail: https://github.com/johngodley/redirection/issues/180

UPDATE: This "suggestion" of mine is incorporated upstream, in plugin itself, so there is no need to modify anything: we now have redirection_url_target and redirection_url_source filters so custom code can manipulate the source and target redirect for special purposes.now there

I also use this plugin, so I figured I'd dig into the code to see if I can find the answer.

There are two actions you could use for this that may work redirection_first and redirection_last

Both take two arguments: $url and $this (which is the wordpress module for the redirection plugin)

Here's the snippet of code from the module init() in \modules\wordpress.php

public function init() {
    $url = $_SERVER['REQUEST_URI'];

    // Make sure we don't try and redirect something essential
    if ( ! $this->protected_url( $url ) && $this->matched === false ) {
        do_action( 'redirection_first', $url, $this );

        $redirects = Red_Item::get_for_url( $url, 'wp' );

        foreach ( (array) $redirects as $item ) {
            if ( $item->matches( $url ) ) {
                $this->matched = $item;
                break;
            }
        }

        do_action( 'redirection_last', $url, $this );
    }
}

So, $url is your requested URL, and in redirection_last, $this->matched has your redirection url in it. I would start with redirection_start and you could run something like:

function redirection_strip_query_string( $url = '', $this ) {

    if ( strpos( $url, '?page=' ) !== false ) {

        $url = preg_replace('/\?.*/', '', $url);

    }

}

add_action( 'redirection_first', 'redirection_strip_query_string' );

Two notes:

1. I have not tested this code.
2. I wanted to give credit to the simple URL preg_replace