If I create several instants, I open the data editor and I select the 3rd element, say, it sometimes deletes the 2nd and 4th, or some other random behavior.
Fixed as of commit 630cb7120480. This was a poor interaction between two ways of updating the same view, resulting in an inconsistent view - the underlying model was edited correctly and shown correctly on the main pane, but the data editor would show the wrong data.
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Also, trying to delete an item from the data editor while playing a file leads to a crash. I'm using macOS 10.13.2
Fixed as of commit 630cb7120480. This was a poor interaction between two ways of updating the same view, resulting in an inconsistent view - the underlying model was edited correctly and shown correctly on the main pane, but the data editor would show the wrong data.
This should be fixed in v3.1, along with the related #250 Data Editor changes the layer type.