BUG use_only_x_path requires CMS user to re-authenticate on publish of page

[muskie9]

This issue has been brought up a couple times and our implementations tend to utilize the use_only_x_path quite a bit and when a page is published it prompts the login overlay within the CMS.

We're reviewing how the code acts with use_only_x_path enabled from a session perspective, mainly surrounding the use of Directory::test() however we have not identified the core issue. Not implementing the `use_only_x_path config option results in normal CMS activity.

[muskie9]

I came across this comment silverstripe/silverstripe-sharedraftcontent#153 (comment) when looking at an unrelated issue and thought it may have some insight into how the session could be invalidated causing the user to have to re-auth.

[jellygnite]

It would be nice to solve the issue with Director::test(), but in the meantime would it be feasible to replace the line
$output[] = Director::test($searchLink);
with a different method.
This module does things a little differently. Looks like it creates a separate session and just renders the page with $page->forTemplate()
https://github.com/wilr/silverstripe-algolia/blob/main/src/Service/AlgoliaPageCrawler.php

I also note from
SilverStripe\ErrorPage\ErrorPage.php](https://github.com/silverstripe/silverstripe-errorpage/blob/1/src/ErrorPage.php

        // Run the page (reset the theme, it might've been disabled by LeftAndMain::init())
        $originalThemes = SSViewer::get_themes();
        try {
            // Restore front-end themes from config
            $themes = SSViewer::config()->get('themes') ?: $originalThemes;
            SSViewer::set_themes($themes);

            // Render page as non-member in live mode
            $response = Member::actAs(null, function () {
                $response = Director::test(Director::makeRelative($this->getAbsoluteLiveLink()));
                return $response;
            });

            $errorContent = $response->getBody();
        } finally {
            // Restore themes
            SSViewer::set_themes($originalThemes);
        }