Thank you for the really fast answer!

This works: 

use Plack::Builder;
use Plack::MIME;

for my $expr (
       ".c", ".cpp", ".css", ".csv", ".dat", ".dpl"
     , ".gp", ".h", ".hpp", ".html", ".ini"
     , ".java", ".js", "makefile", "Makefile", ".m", ".mac"
     , ".pl", ".pm", ".pod", ".py", "README", ".sch", ".sh", ".txt") {
  Plack::MIME->add_type($expr => 'text/plain');
} 
 
builder {
  enable 'Plack::Middleware::Static',
    path => qr{^/html/downloads/},
    root => '.'; 
      
  enable 'Plack::Middleware::Static',
    path => qr{^/html/(?!downloads).*\.(css|gif|jpg|js|pdf|png)$},
    root => '.',
    content_type => sub { Plack::MIME->mime_type($_[0]); }; 
    
  mount "/" => $app1;
  mount "/imggenerator.pl" => $app2;
};

[download]
But I'm far from really understanding it and there still is one issue: .html in downloads are still treated as html files, not as plain text.

In reply to Re^2: How to use Plack::Middleware::Static by vhein79
in thread How to use Plack::Middleware::Static by vhein79

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