Windows 2008 R2
IIS 7.5
MediaWiki 1.35.1
PHP 7.3.25
MariaDB 10.3.27

Hello,
I'm having an issue that is quite same like T261921, however I'm running my installation on Windows server on IIS.

Editing pages without / is fine and VisualEditor works, but when it contains / I'm getting 404: Error contacting the Parsoid/RESTBase server (HTTP 404)

In the log appears:

[http] GET: https://my.domain.com/wiki/dev/rest.php/my.domain.com/v3/page/html/Product%3APortal_Changelog%2F2021.1.0/2867?redirect=false&stash=true

When I open the URL in the Chrome on the server I get the following response:

{"messageTranslations":{"en":"The requested relative path (/my.domain.com/v3/page/html/Product:Portal_Changelog/2021.1.0/2867) did not match any known handler"},"httpCode":404,"httpReason":"Not Found"}

Note: As a temporary solution is to switch back to external Parsoid service that I used on 1.34 before the upgrade.

Thank you