Update readme

README.md

@@ -49,11 +49,31 @@ nix-shell
 ```
 This will fetch all development dependencies (NodeJS, the SCCD compiler, some NPM packages) and you will enter a shell with all environment variables set such that it will appear as if those dependencies are installed on your system. (Your system state is however unaltered).
 
-Then, run `scripts/dev_server.sh` to start a development server.
+Then, run `scripts/dev_server.sh` to start a development server. Navigate to `http://localhost:8700`
 
 There are 2 other (build) scripts in the `scripts` directory. The reason is as follows: In the original drawio repository, build outputs are placed in the source tree, and committed into the repository, giving us 2 options:
 
   1. Rewrite drawio's build script to become pure, such that Nix can take care of the build for us.
   2. Require developers to run the build script from a development shell, and `git add`/`commit` the build output.
 
-We chose option 2, simply because rewriting drawio's build is outside of the scope of this project.
+We chose option 2, simply because rewriting drawio's build is outside of the scope of this project.
+
+## Running
+
+When you are running the backend server (either after building the server package or running a development server), navigate to <http://localhost:8700> to load the frontend.
+
+### Plugins
+
+2 custom plugins are available that are not part of upstream drawio.
+
+#### Collab
+
+Extends the UI with a collaboration menu, to allow "share by link" and multi-user, synchronous collaboration.
+
+To use this plugin, navigate to <http://localhost:8700/?p=collab>.
+
+#### FTG+PM
+
+Adds a set of primitives to the library panel on the left for the concrete syntax of the FTG+PM formalism. Additionally, creating arrows between FTG+PM primitives will automatically update the style of those arrows to be consistent with the FTG+PM notation.
+
+To use this plugin, navigate to <http://localhost:8700/?p=ftgpm>.