Duplicator 1.5.4 – 400 Bad Request

Hello, we just installed Duplicator 1.5.4 – and we are getting a 400-Bad-Request. The culprit seems to be the filename “main.installer.php” that Duplicator installer.php uses – I believe it’s intrepretting the “.” after “main” as a file extension, and creating this error. I know it’s this file because the error shows up with the filename in the URL of the browser. I don’t get this msg if I change filename to “main-installer.php” (though this leads to other problems).

We are on Siteground using WP 6.2.2, PHP Version 7.4.33.

Previous versions of Duplicator installer.php did not contain references to “main.installer.php”

Thank you!

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