When the Editor doing importing magic, the progress window has a "Cancel Batch" button to cancel the process. However, this button can never be used.
Note: it only happens to the "Cancel Batch" button. Others like "Stop Transcoding" for video have no such issue.

Repro:
1. Open attached project
2. Observe the button and try to click on it

If you have other platform support installed for the Editor, like iOS.
3. Press Ctrl + Shift + B to call out the Build Setting window
4. Switch target platform to iOS
5. Observe the button.

Expected:
User can cancel the platform target switch or launch project process by clicking "Cancel" button

Note: There are other places the importing process is engaged. These are the easiest to see.