Fly - through / Drone Perspective View Mode Added
Finally figured out how to add a drone-type fly around mode. It was not easy, maybe getting too close to creating my own game engine... Now, from the Modify Visualization panel, if you choose "Explorer" as your View Mode, you can move through the scene in 3D. For example, with the Oceanside example, your starting "View Mode" view will look like this:

You can "fly" through the scene using the W [forward], S [backward], A [pan left], and D [pan right] keys to move. You can also hold the left button on your mouse and move around. To change your view direction, hold the right mouse button and move the mouse around. To move vertically up and down, use the wheel on your mouse, or the trackpad zoom-in (pinch) gesture. All other viz features work as they did previously. Note that if you want to lock the camera position to the ground - to simulate walking / driving around - add "renderLocktoGround" to your config.json file, and set the value to 1 (integer).
Here is a fun landslide tsunami animation using this 3D view: https://youtu.be/3X1edF9A5kY

Hey Mathieu. Fixed - that was happening because the View Type drop-down box was still selected, and when pressing "D" , the UI would first apply that to the drop-down menu, and select Design (first letter D) mode from the menu. Easy fix. LMK if it is still happening.