autotutorial

read all about this guide.
https://wordpress.org/support/topic/read-this-first-wordpress-5-2-master-list/

https://wordpress.org/plugins/media-library-plus/

always make backups of files and databases before any changes are made
https://codex.wordpress.org/WordPress_Backups

also changing the scheme the url is modified and consequently it changes in general settings and with the help of a plugin you change the url of the posts, articles in https
https://codex.wordpress.org/Moving_WordPress#Changing_Your_Domain_Name_and_URLs
Example old url http://old_domain.com/ with plugin search and replace it without end slash https://old_domain.com
the prefix www. it also makes a difference in a url context.

Here we are now finished. 🙂

This procedure is good for installations from wordpress.org otherwise asking your hosting if the use of the CloudFlare plugin can break the site.
1a)If you have already requested the certificate with Flexible SSL, it will be created within 48 hours, making sure you have selected Flexible SSL.
1b)Download and activate the Cloudflare plugin
2)Set off the automatic rewrites, always use https, Create PageRule to exclude WordPress’ dashboard from Cloudflare.
3)Follow the steps in “Use Cloudflare’s SSL certificate on your site.” Except for setting the port to 443, Flexible SSL plugin and create a Page Rule to redirect all traffic from HTTP to HTTPS
4)

RewriteEngine On
RewriteBase /
RewriteCond %{HTTP:X-Forwarded-Proto} !https
RewriteRule [^/]? https://yourdomain.com%{REQUEST_URI} [R=301,L]

Obviously first you have to change the url in https from general settings.
Your site now use always https.

If something goes wrong to go back to http you need to remove the define('FORCE_SSL_ADMIN', true);
Add the define of home and site in wp-confing.php and delete the htaccess rule for rewriting in https without disable or delete the plugin

*Note The universal certificate only works on browsers with SNI support.

• This reply was modified 7 years ago by autotutorial.

Backup your files and database https://codex.wordpress.org/WordPress_Backups
If the url has changed you have to change the url in the new installation https://codex.wordpress.org/Moving_WordPress#Changing_Your_Domain_Name_and_URLs (Not touch other except Dashboard, wp-config.php or database https://codex.wordpress.org/Changing_The_Site_URL). Please only Dashboard, wp-config.php or database.
Then, with a plugin, it changes the URL of the post,article etc.. follow the link indicated don’t go ahead if you can’t do backups.

If you use a cache plugin try disabling it from ftp wp-contens/plugin/yuorplugin/, or database

internationalized Domain Name https://www.php.net/manual/tr/function.idn-to-ascii.php
internationalized Path https://en.wikipedia.org/wiki/URL
Any utf-8 character that does not cover the characters available in the path will be converted to %HH percent-enconding.

https://domain3.com/wp-login.php?redirect_to=https%3A%2F%2Fdomain3.com%2Fwordpress%2Fwp-admin%2F&reauth=1
Yes this is right.
With the variable $_SERVER[‘HTTP_HOST’] it is not safe but with the empty value in the define it is safe.

I looked at the source code for subdirectory installations the DOMAIN_COOKIE does not seem important for the multisite subdirectory and normal installation constants but in the network.php if the www prefix is ​​present. it will be expanded to the root of the domain example http://www.domain.com will be set for .domain.com (it will be visible on any subdomain) therefore it is better to set the define also with empty value.

define( 'WP_ALLOW_MULTISITE', true );

define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', false);
define('DOMAIN_CURRENT_SITE', 'www.domain1.com');
define('PATH_CURRENT_SITE', '/wordpress/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

define('COOKIEPATH','');
define('SITECOOKIEPATH','');
define('ADMIN_COOKIE_PATH','');
define('COOKIE_DOMAIN','');

The multisite creates other tables in the dababase like wp_x_options where x does not necessarily have to be an incremental number COOKIEPATH should be the home, SITECOOKIEPATH site also for non multisite installations obviously the table for the latter is wp_options. I put the empty value on ADMIN_COOKIE_PATH should be the value of SITECOOKIEPATH for multisite installations subdirectory otherwise it is SITECOOKIEPATHwp-admin.

You have the network on the wordpress folder and this cookie should be in the wordpress folder while for mapped sites it depends on whether it is in root or other folders.I offer no guarantee on direct or indirect malfunctions, these are only reflections of these codes.
https://github.com/WordPress/WordPress/blob/master/wp-includes/ms-default-constants.php#L50
https://github.com/WordPress/WordPress/blob/master/wp-includes/class-wp-network.php#L299
https://github.com/WordPress/WordPress/blob/master/wp-includes/default-constants.php#L219