Avoid multiple redirects in contao - .htaccess

Question

I have analyzed my website with the portal web.dev from Google. This told me that I have too many redirects if I call the URL without www and with http:
It goes first to https and without www, then to http with www and only then to https and www.
This is my htacces file:
<IfModule mod_headers.c>
# Allow access from all domains for webfonts (see contao/core-bundle#528)
<FilesMatch "\.(ttf|ttc|otf|eot|woff2?|font\.css)$">
Header set Access-Control-Allow-Origin "*"
</FilesMatch>
</IfModule>
<files serviceaccount.json>
Order allow,deny
Deny from all
</files>
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_URI}::$1 ^(/.+)/(.*)::\2$
RewriteRule ^(.*) - [E=BASE:%1]
RewriteCond %{HTTP:Authorization} .
RewriteRule ^ - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
RewriteCond %{ENV:REDIRECT_STATUS} ^$
RewriteRule ^app\.php(?:/(.*)|$) %{ENV:BASE}/$1 [R=301,L]
RewriteCond %{REQUEST_FILENAME} -f
RewriteRule ^ - [L]
RewriteRule ^ %{ENV:BASE}/app.php [L]
</IfModule>
I don't see at all where these redirects are implemented. I also found this variant to redirect directly. Even if I put them in the htaccess file, the redirects remain as described above.
<IfModule mod_rewrite.c>
RewriteCond %{HTTPS} off [OR]
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteCond %{HTTP_HOST} ^(.*)$ [NC]
RewriteRule (.*) https://www.%1/$1 [R=301,L]
</IfModule>
Can you tell me how all these redirects come about and why the last code snippet doesn't work?

Answer 1

Some of those redirects might be done by your Hoster. Also, in newer Contao versions, Contao automatically redirects to https in the front end, if HTTPS is enabled in the respective website root's settings in the back end.
In any case, you should implement the redirects yourself, e.g. in your web/.htaccess. For example:
# Redirect to www subdomain
RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteRule ^ https://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
# Redirect to HTTPS
RewriteCond %{HTTPS} off
RewriteRule ^ https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
Note: the www redirect would redirect any domain that does not start with www. to www.. If you have a multidomain setup with different subdomains, you will need to adjust the www. redirect accordingly.