When editing a non-dynamic timeline, you can choose ‘delete widget’ but the confirmation popup shows BEHIND the playlist timeline popup so it cannot be confirmed or denied.
I have tried to recreate using the latest version which there appears to be no issue. There have been a number of issues addressed since v3.0.3,so it maybe wise to upgrade your CMS to see if this solves it for you, v3.1.3 being the latest.
I’m having the same bug with v3.1.3. I’m editing a playlist timeline and I try to delete a widget, but the (modal) windows to confirm the deletion appears behind. When I close the timeline, the modal windows keeps there but loses its context and it hangs when I confirm the deletion.