Fix more links

docs/API/pleroma_api.md

@@ -124,7 +124,7 @@ Request parameters can be passed via [query strings](https://en.wikipedia.org/wi
 ```
 
 ## `/api/pleroma/admin/`…
-See [Admin-API](Admin-API.md)
+See [Admin-API](admin_api.md)
 
 ## `/api/v1/pleroma/notifications/read`
 ### Mark notifications as read

docs/installation/otp_en.md

@@ -42,7 +42,7 @@ apk add curl unzip ncurses postgresql postgresql-contrib nginx certbot
 ## Setup
 ### Configuring PostgreSQL
 #### (Optional) Installing RUM indexes
-RUM indexes are an alternative indexing scheme that is not included in PostgreSQL by default. You can read more about them on the [Configuration page](config.html#rum-indexing-for-full-text-search). They are completely optional and most of the time are not worth it, especially if you are running a single user instance (unless you absolutely need ordered search results).
+RUM indexes are an alternative indexing scheme that is not included in PostgreSQL by default. You can read more about them on the [Configuration page](../configuration/cheatsheet.md#rum-indexing-for-full-text-search). They are completely optional and most of the time are not worth it, especially if you are running a single user instance (unless you absolutely need ordered search results).
 
 Debian/Ubuntu (available only on Buster/19.04):
 ```sh