Teamcenter Visualization Markup Layers are no longer visible in TcVis after closing the Markup Layers Window

After closing a Markup Layers Window the TcVis Markup Layers are no longer visible and sending Markup Layers to a new window no longer works.

This is working by design and here is why.

Using TcVis 12.3.0.9 as an example I open block.jt from the 3D examples. Then I create an anchored 3D text markup:

I then right-click on the Markup Layer > Send to Window:

Now I have it in a separate window and the markup layer is gone from the assembly tree:

When you do this the Markup Layers now act like a dockable window. You can see that if you go to Menu > View > Docking Windows it is now treated like its own window that can be docked or floating with the checkmark below:

So when you do this and close your session and then create a new 3D markup, if this window was closed in your last session it acts no differently than say the Attachments or Window Properties windows. And if you want to get it back in the Assembly Tree, turn it on and then RMB and choose “Return To Tab”:

When you do that now it acts like the traditional use of the Markup Layers in the Assembly tree: