Flip PDF embed inside templates
You'll need to create custom route to access those files. This is just an example of a custom route in my current module, so you need to find a pattern that matches the one you receive from the tool

$event-&gt;rules[] = [
    'pattern' =&gt; '/userfiles/&lt;fileType:\w+&gt;/&lt;fileName:\S+&gt;',
    'route'   =&gt; 'thaff/profile/get-file'
];


And your Controller action could be something like this

public function actionGetFile($view, $fileName)
{
    // create an alias to your folderpath $view should be thumb/mobile-ext or mobile depending on the route
    $localPath = Craft::getAlias('@yourFolderAlias') . DIRECTORY_SEPARATOR . $view;

    // you can include several checks if the image should be visible for the current user or not...

    $resp = Craft::$app-&gt;getResponse();
    $resp-&gt;headers-&gt;set('Content-Type' /*, insert your mime-type here */);
    $resp-&gt;format = Response::FORMAT_RAW;
    // check if the file exists
    if ($localPath &amp;&amp; file_exists($localPath . $fileName)) {
        // open the file
        $handle = fopen($localPath . $fileName, 'rb');
        // send the result to your response object
        $resp-&gt;stream = $handle;
        // send the response and close the file
        $resp-&gt;send();
        @fclose($handle);
    }
}


Note: this is just a little code snipped of my current project and I removed many conditional checks so it's easier to read.