Views menu > Activate All Maps

Activate All Maps turns on the Show Map In Viewport flag for all materials assigned to the scene.

To undo this action, use Views menu > Deactivate All Maps. This will turn off the maps for all materials. If you only want to turn off individual maps, you need to turn off Show Map In Viewport in the Material Editor.

Note: This command does not apply to XRef objects and objects in XRef scenes.