Compendium
The Compendium displays organized content loaded into the framework. To open it, click the 
Compendium button on the Minimenu, or press the F12 hotkey. You can dock it on the side and access it at all times.
Clicking on the Compendium title will reload the content in case any change is made and not updated. Some content will be hidden for the players, that content will be highlighted gray, some of those hidden content can be configured from the Framework Settings in "Player Permissions". Others have to be changed individually, like maps, tables and notebooks.
The search bar can search any content loaded in the framework, Classes, Characters, Monsters, Spells, Maps and others. Type the name or part of the name and it will display any matching result, letter case, spaces and other symbols are ignored, so fire ball and Fireball is considered the same entry.
Displays all player characters and allows new PCs to be created, clicking on it's name will open the character's Statblock and you can create a new token for that character from there.
Displays all notebooks found on the campaign, as well as notebook pages, clicking on each page will open it, or click the notebook name to open it's index. If the notebook has a color label it will also display it's color. More notebooks can be added from the "+" link.
This section displays all races loaded by default, more can be added from the Framework Settings. Clicking on a race opens a window with that race's features, and can be added to a player from there.
Displays all Classes and Subclasses loaded by default, more can be added from the Framework Settings. Clicking on a Class opens a window with that class's features and subclasses, each feature can be added to a player from there.
This section displays the default background loaded, more can be added from the Framework Settings. Clicking on a background opens a window with that background's features, and can be added to a player from there.
Displays all equipment loaded, separated by Weapons, Armor, Adventuring Gear, Tools, Mounts & Vehicles and everything else not on these categories go to Magic Items (if they are magic) or Other (if they are not), more can be added by clicking on the + link on any of the equipment windows.
Displays a window with spells sorted by by class and level, more spell lists can be added on "Spellcasting classes" and and edited in "Spells by level", from each list, spells can be added to a character's sheet.
Displays a window with explanation on feats in general and a default feat, more can be added from the Framework Settings.
Displays specific optional class features such as fighting styles, invocations and channel divinity, more can be added from the Framework Settings.
Opens a window with all loaded and indexed NPCs, and more can be created or loaded into the map using the New NPC button. From the Creature List window, creatures can be sorted by name, type, CR or book source. If new creatures are added to the compendium, you need to click "Build Table" to index the new creatures so they can be displayed.
Displays all maps on the campaign, clicking on each map will open it, more can be added from the "Map>New Map ..."
Displays all MapTool Tables, opening each table will open a window with that table's contents rendered, and offer a dice roller that rolls and displays the rolled results. More tables can be added from the "Window>Tables" panel.