Add note about workflow_dispatch has to be on default branch

README.md

@@ -200,7 +200,10 @@ on:
 1. Rewrite the docker build workflow `build.yml` to only be done on main and rewrite the build and lint workflow `test.yml` to only run on PR changes
 2. Create a new feature branch, add a new commit with a dummy change (to any file) and finally create a PR to main. Verify that the `test.yml` workflow is run on the feature branch. Merge the PR and verify that the `build.yml`-workflow is only run on the main-branch.
 3. Update the `test.yml` workflow and add the event for triggering the workflow manually. Make sure to push the change to main-branch.
-4. Go to the [GitHub Actions page of the workflow](/actions/workflows/test.yml) and verify that the workflow can be run manually
+4. Go to the [GitHub Actions page of the workflow](/actions/workflows/test.yml) and verify that the workflow can be run manually. A `Run workflow` button should appear to enable you to manually trigger the workflow. 
+
+    > [!NOTE]
+    > In order for the `Run workflow`-button to appear the workflow must exist on the default branch, typically the main-branch
 
 ## Manually triggering workflows