Once there were a bug redirecting HTTP traffic to HTTPS. I know it's done not by mod_rewrite but when changing site's URL in conf_global.php from HTTP to HTTPS.
But now when somebody has an old link to some images to my site it still uses HTTP and theres no redirect. And if I want to correct it with mod_rewrite by adding

RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [R=301,L]

Then I have another problem. If somebody comes to my site from HTTP, it takes them to index.php instead.

The thing is that I'd like to add 301 redirect to HTTP links but right now it's not entirely possible (https://redirect.miljonivaade.eu/?url=www.invisionpower.com).

Is there any solution?

THis article might help: https://www.sslshopper.com/apache-redirect-http-to-https.html