Don't ask me how I found this bug (it drove me mad not knowing how to recreate it at first), but there's some weird behavior going on with multi-comp editing.

Steps to reproduce:

1. Create a new design file
2. Add a body tube, close the config dialog
3. Add a second body tube, don't close the config dialog
4. With the second body tube selected, Ctrl/Cmd- or shift-click on the first body tube in the component tree so that both body tubes get selected and you're in multi-comp edit mode
5. Change the length to a different value than the default one
6. Close the config dialog
7. Undo the operation (either hit Ctrl/Cmd + Z, or 'Edit > Undo')
8. Select the second body tube
9. Hold the shift-key and double click on the first body tube, the multi-comp edit dialog will appear
10. Play with the length slider, you'll see that the rocket view does not update
11. Enjoy this bug, it's a really fun one, try for instance switching to a different rocket view if you set the length in step 10 to a smaller value than the default value. Floating tubes :'))))

Demo: