diff --git a/doc/README.Swagger b/doc/README.Swagger
index 576339a5e..f32df2f48 100644
--- a/doc/README.Swagger
+++ b/doc/README.Swagger
@@ -7,7 +7,17 @@ http://petstore.swagger.io/ or http://editor.swagger.io/
 You may as well set up your own swagger-ui installation as described at
 https://medium.com/@tatianaensslin/how-to-add-swagger-ui-to-php-server-code-f1610c01dc03
 
-Your apache needs to have the module 'header' enabled, because some HTTP headers
-are set when the file swagger.yaml is accessed by the editor.
+Your apache needs to have the module `header` enabled, because some HTTP headers
+are set when the file `swagger.yaml` is accessed by the editor.
 
 Currently, the swagger.yaml shipped with SeedDMS uses still swagger 2.0
+
+If you are using php-fpm you will have to ensure that files with
+extension .yaml are allowed to be parsed. Extend the
+`security.limit_extensions` in the pool configuration by `.yaml`. Also
+check the contents of the file `.htaccess` in directory `restapi`. It
+by default sets the handler for php to `application/x-httpd-php` which
+uses the apache module of php. If you would like to use php-fpm
+instead, then set it to
+
+    SetHandler "proxy:unix:/var/run/php/php8.2-fpm.sock|fcgi://localhost/"