#2196 document how to configure the MIME type of the server

projects/ngx-extended-pdf-viewer/troubleshooting.md

@@ -8,6 +8,53 @@ There's also a layout glitch that seems to be intentional: you may need to set t
 
 If you run into problems using `<ngx-extended-pdf-viewer>`, please open an issue on the [project bug tracker](https://github.com/stephanrauh/ngx-extended-pdf-viewer/issues).
 
+## "Failed to load module script: Expected a JavaScript module script but the server responds with a MIME type of "text/plain"
+
+Update your server configuration. Many servers don't recognize `*.mjs` files as JavaScript. To fix this, you have to configure the server so it sends the file with the proper MIME type (`text/javascript`). You also have to configure the new i18n files. They've got the file ending `.ftl` and need the MIME type `text/plain`.
+
+For example, IIS requires this configuration:
+
+```xml
+<?xml version="1.0" encoding="utf-8"?>
+<configuration>
+
+<system.webServer>
+ <staticContent>
+  <mimeMap fileExtension=".mjs" mimeType="text/javascript" />
+  <mimeMap fileExtension=".ftl" mimeType="text/plain" />
+ </staticContent>
+</system.webServer>
+
+</configuration>
+```
+
+nginx requires this configuration:
+
+```json
+location / {
+    ...
+
+    location ~* \.mjs$ {
+                # target only *.mjs files
+                # now we can safely override types since we are only
+                # targeting a single file extension.
+                types {
+                    text/javascript mjs;
+                }
+            }
+  }
+```
+
+AWS amplify requires this configuration in the `amplify.yaml` file:
+
+```yaml
+customHeaders:
+  - pattern: '*.mjs'
+    headers:
+      - key: 'Content-Type'
+        value: 'application/javascript'
+```
+
 ## Compatibility to Bootstrap (and other CSS frameworks)
 
 Bootstrap interferes with the printing algorithm of `pdf.js`. Guard it with a media query to avoid unwanted effects, such as scaling the print to 65%. For example, if you're using SCSS and Bootstrap 4, remove the import of Bootstrap.min.css from the Angular.json file. Instead, import it by including Bootstrap by adding this line to the global `styles.scss` file: