<code>The user is unable to add multiple content types to the shortcut bar by clicking the "add shortcut" star icon. This can be worked around by adding the shortcut manually via "Edit Shortcuts", but it is confusing as it stands. This does not seem to be a problem in D7. Here are a couple of animated gifs that demonstrate different behaviour between D7 and D8.
D8 - adding shortcuts via star icon
D7 - adding shortcuts via + icon
Steps to replicate.
1. Go to node/add/page
2. Click the star icon to add shortcut
3. Go to node/add/article
4. Star icon is already activated. Clicking it removes the page shortcut added earlier.