i modified the .htaccess via the plugin ReallySimpleSSL and now obtain this:
i confirm that without your theme and wp 2017 theme all is working well.

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Options:
* htaccess redirect
* WordPress redirect
* Mixed content fixer
SERVER: apache
SSL is enabled for this site
** Detecting configuration **
plugin version: 3.0.5
Already on SSL, start detecting configuration
Opening testpage to check server configuration: https://virtuadev.fr/wp-content/plugins/really-simple-ssl/ssl-test-page.php
test page url, enter in browser to check manually: https://virtuadev.fr/wp-content/plugins/really-simple-ssl/ssl-test-page.php
Could not open testpage cURL error 28: Connection timed out after 5001 milliseconds
SSL type: LOADBALANCER
** Configuring SSL **
testing htaccess rules…
test page url, enter in browser to check manually: https://virtuadev.fr/wp-content/plugins/really-simple-ssl/testssl/loadbalancer/ssl-test-page.html
htaccess rules test failed with error: cURL error 28: Connection timed out after 5000 milliseconds
checking if .htaccess can or should be edited…
.htaccess does not contain default Really Simple SSL redirect
retrieving redirect rules
converting siteurl and homeurl to https