Invalid URL during WordPress New dashboard widget operation

Somehow this URL is formed:

https://*.com/wp-admin/admin-ajax.php?action=dashboard-widgets&widget=dashboard_primary&pagenow=dashboard&{%22pll_ajax_backend%22:1,%22pll_post_id%22:7}

Steps to reproduce:

1. In Screen Options hide WordPress News on the Dashboard
2. Delete its transient called _transient_dash_*, use Option Inspector or wp-cli
3. In Screen Options select WordPress News for showing on the Dashboard

You get the URL above in an AJAX request.
https://tools.ietf.org/html/rfc3986#section-2.2 shows that { and } should be URL-encoded.

My WAF gets sad about it and bans the user.

I think appending &pll_ajax_backend=1&pll_post_id=7 was intended.
I am not able to understand the JS in admin/admin.php

Thank you for fixing it.

https://www.ads-software.com/plugins/polylang/