Editors
Click the orange pencil to start editing, and the save button (or Control-S) to save.
Every Editor in Campaign Builder has the same basic functionality, which includes the normal formatting options as other Foundry editors, as well as some additional capabilities:
Autocomplete Mentions
There is a separate module - Autocomplete Mentions that is not needed but can be highly useful for campaign and world building. It enables you to type '@' and easily search for the characters, locations, and organizations in your campaign and then insert them as a link in any editor field.
This can be doubly helpful in Campaign Builder because of the auto-suggest capabilities of the Campaign Builder editors.
Drag and Drop
You can drag any Entry, Campaign, or Session, from the Setting Directory into the description editor, and it will insert a UUID indicator that when you save will be displayed as a clickable link that will open that Entry (hold 'Control' while clicking to open it in a new tab). Similarly, you can drag any Foundry document (ex. Actors, Journal Entries, etc.) into the description editor for a link to that document (the same way you can in other Foundry editors).
Automatic references
When you save an editor, if you have exactly (but case insensitive) used the name of any Entry or Session (other than the current one), it will automatically turn it into a reference link.
NOTE
If you have more than one Entry or Session with the same name, it will not create a link, so that it's not linking to the wrong one. Instead, use Drag & Drop or Autocomplete Mentions to insert a reference to the one you want. This is likely to be a very rare situation, though.
Auto-suggest relationships
If you insert a reference to an Entry into the description of another, you will automatically be asked if you'd like to create a relationship. This allows you to connect two entries or to mention an entry in a session note (which will then also add it to the campaign To-do list) with just a couple keystrokes.
NOTE
It will not suggest connections to the parent of the current Entry. This is deliberate to avoid cluttering the relationship list and unnecessarily prompting about automatically creating the relationship. The Entry's parent is easily available from the directory tree, so it didn't seem to add much value to link it in the editor. Submit a feature request if you disagree.